Soon, a police patrol arrived and two officers made their way towards to the large, powerfully built figure lying face-up on the bitumen. One of the officers recognised Hodge: a factor, he says now, that - combined with the way ACT Policing handled him that night - probably saved his life.

Under the gaze of nearby diners in the trendy Canberra restaurant district of Kingston, Hodge begins to sob. "I was hoping a car would run me over," he explains. "I just started bawling my eyes out, saying, 'I need help, I need help'."

Hodge clamps his eyes shut as he tells the story and he freezes momentarily in his chair. After a long pause his tightly clenched face eases a little and he lets out a low sigh, as if waking from a trance. "Sorry, it's this medication I'm on. It makes me twitch and close my eyes every so often."

Today is a good day for Hodge. A fortnight ago he asked a friend to call and postpone our interview. Hodge had been overwhelmed by an anxiety attack after getting into a shouting match with a passing motorist while riding his bike. Now he's leading me down the corridor of his home to the "war room" - the label his wife has given it. In one corner of the room hangs a blue United Nations beret. In another, the butt of a MAG 58 machine gun is mounted on a board. Plaques, glass-framed certificates, awards, photos and scraps of newspaper articles adorn every wall. Walking into the room feels like stepping into a monument to a cherished, lost way of life.

So how did it all unravel so quickly? How did this promising career, hallmarked by a rapid rise through the ranks, end by the age of just 37?

Hodge, a veteran of multiple deployments with both the army and the Australian Federal Police, is one of the hundreds of Australian soldiers who, on returning home, find themselves haunted by post-traumatic stress disorder.

With Australia's decade-long war in Afghanistan coming to an end, all but a handful of the troops are returning home. For most who made it back in time for Christmas it will mean a welcome return to the routines of family life and work. For others, it will mark the start of a new, silent war that they cannot return from, played out in the homes they find themselves unable to leave, medically discharged from the jobs they love in their early 30s, and wracked by night terrors, panic attacks and isolation.

Post-traumatic stress disorder [PTSD] is one of the most common psychiatric disorders in Australia. Most Australians are likely to have at least one traumatic experience during their lives, and 5-10 per cent of those who do are likely to develop PTSD, according to the Australian Centre for Posttraumatic Mental Health. The Department of Veterans' Affairs (DVA) says 1713 veterans of recent conflicts are suffering from PTSD, and of those, 955 are veterans of either the Afghanistan or Iraq conflicts.

But Katie Tonacia, a co-founder of PTSD support group Picking Up the Peaces, says the real number is likely much higher, with many sufferers developing symptoms years after leaving the service.

"I think it's a bigger problem than any of us really know," she says. "We will see a lot of people falling apart at retirement age, because it's that organisation, that structure that has kept them upright, kept them getting out of bed every morning. The stigma of not wanting to be labelled as having a disorder also makes it almost easier to be alone at home and withdraw, [rather] than face that fear of going out."

Of the more than 45,000 Australians who have served in conflicts since 1999, the Department of Defence estimates that nearly one in five will suffer a mental disorder. Around half will come forward seeking treatment in the short to medium term. But expert evidence provided to the Australian parliament in 2013 suggests the actual numbers seeking treatment may be closer to 25-30 per cent, in line with the United States experience.

"Our efforts to educate and encourage our people to seek help as early as possible may also gradually increase the number of those seeking treatment," says a Defence spokesman.

Addressing the inquiry into the care of personnel wounded or injured on operations, former commander of Australian forces in the Middle East, Major General John Cantwell - himself a PTSD sufferer - warned of a flood of soldiers from Afghanistan and Iraq presenting with serious psychological damage in the coming years. "The numbers will grow, and grow exponentially," he says. "We have exposed thousands of young and old Australians to some pretty brutal experiences. There is a large wave of sadness coming our way, and the system - DVA and Defence - needs to be ready for it. I wonder whether we are?"

Chad Dobbs doesn't think so. The signals specialist was deployed to Iraq in 2006. At the age of 26, after switching from command post duties, it was exciting to be sent into the field on patrols. Then the roadside bomb attacks began. "I was in a convoy of about 40 vehicles, in front in the commander's vehicle," Dobbs says. "The Iraqi security forces led us down a road as their escort, they went through the checkpoint and we didn't."

Two bombs ripped through the convoy, destroying two vehicles and showering Dobbs in debris, pinning his group down for the next 24 hours as they attempted to evacuate a colleague whose leg had been shattered by the blasts.

Seven months later and back at base in Darwin, life was slowly getting back to normal. Following a successful round of further training and a promotion to the rank of lance-corporal, Dobbs received a summons from his squadron commander. His skills were needed again, this time in Afghanistan with the 7th Battalion, Royal Australian Regiment.

It was during that trip that his friend Corporal Mathew Hopkins was gunned down. Hopkins had been on a patrol near the village of Kakarak, 12 kilometres north of the Australian base at Tarin Kowt, when he was shot in the head during a firefight with the Taliban. Days later, a heart-breaking photo of the 21-year-old soldier nursing his newborn son, Alexander, was plastered across Australian media. The two had spent just four days together during a break from deployment.

"On a day-to-day basis not a lot happens on patrol," Dobbs says. "A lot of young guys just cruise around in Bushmasters and ASLAVs [Australian Light Armoured Vehicles]. They don't get out on foot, so their war experience is driving around the desert, waving at locals and sitting back in the car. I think for a lot of them, Mathew's death really brought home that we were in Afghanistan and that we were at war."

Reeling from the loss of his friend, Dobbs returned to Australia in 2009, exhausted both physically and mentally by his experiences. It wasn't long before his world began to fall apart.

"I didn't really notice the changes until I got home," he says. "I was having anxiety attacks; there would be times when I just couldn't get out of bed. There were times when I would drink before work, I couldn't control my anger."

After several days of not sleeping and heavy drinking that almost ended with him deliberately wrapping his car around a pole, he reached out to the senior soldier at his unit for help.

"Instead of the words of encouragement and avenues of support I expected from a person of that rank, I was met with, 'Harden the f... up and get over it' ." Alone, with a relationship crumbling around him and unsure where to turn for help, he descended into four months of isolation where he withdrew from family, friends and workmates, until one day he found himself in hospital, coming out of a week of heavy sedation and being prescribed aggressive-behaviour counselling to try to bring him back from the edge. Not all his comrades have been so fortunate. Dobbs says he's aware of a spate of recent suicides among returned Iraq and Afghanistan veterans that has gone largely unreported.

Official figures show that since 2000, 92 ADF members are suspected or confirmed to have died by their own hand. But Defence doesn't keep any records of those who die from suicide once they leave the armed services.

A seven-year, $13.5 million study into the impact of service on the health and welfare of the families of deployed ADF members is expected to be published in 2014, although another report, published in 2000, found the children of those deployed to Vietnam were three times more likely to commit suicide than members of the general community. A 2005 study also found national service veterans were 43 per cent more likely to die from suicide than non-veterans.

Veterans' Affairs says it has no formal system for tracking those who have left the ADF, relying instead on its At Ease website and YouTube videos as a way of keeping in touch with and supporting former personnel suffering from PTSD. It also covers medical and other costs for those diagnosed with PTSD.

Both Veterans' Affairs and Defence have also significantly increased their research and expenditure on mental-health issues in recent years, completing or commissioning a number of research studies. Veterans' Affairs spends more than $166 million a year on medical and support services for veterans. Defence has also increased its mental-health workforce by 50 per cent since 2009.

Despite the increased focus, Dobbs believes the two organisations are still underestimating the number of soldiers affected by PTSD, due to the stigma of coming forward to seek help.

"I have a lot of friends who have had anxiety issues and depression and haven't spoken out about it because it's a career killer," Dobbs says. "My career was put on hold for 2 1/2 years while I actively sought to leave Darwin."

One of the other barriers facing many young war veterans returning from Afghanistan and Iraq is that they don't feel they belong in the RSL clubs or support structures set up following the World Wars and the Korean and Vietnam Wars, leaving them unsure of where to turn for help.

One group that has had more success than most at getting through to younger PTSD sufferers is Soldier On, set up in 2012 to fill that gap. Last year in Adelaide, the charity opened the first of what it hopes will become a national network of reintegration centres - places designed as a one-stop shop to help wounded personnel get in touch with support services.

Co-founder John Bale says the organisation was caught off-guard with the response; it reached its expected half-year target for walk-ins in just over a month. "We think thousands are going to be impacted," says Bale of the number of soldiers likely to be affected by PTSD when they return from deployment. "We were shocked, we really didn't expect as many as we got. There are people who have been isolated for way, way too long. In many instances, we really haven't learnt the lessons from Vietnam, and now is the opportunity for us as a community to make sure we don't have those same issues."

Bale points to US research that shows many PTSD sufferers won't show any symptoms until, on average, 13 years after their deployment, and in many cases it will be decades before a trigger sets off that trauma. A constant stream of Vietnam War veterans continues to come forward in Australia today, nearly 40 years since that conflicted ended. "I think it was the inability of the community to reintegrate veterans that caused many of those issues," says Bale. "And I don't think people have really grasped yet what's happened overseas [in Afghanistan and Iraq]."

Graham Walker, national research officer with the Vietnam Veterans Federation of Australia, agrees, and says the true extent of the trauma caused in Iraq and Afghanistan is unlikely to be fully realised for a decade or longer.

"For combat troops, the traumatic effect is cumulative. What happens is you go to the war, and when you come home, you kind of don't get back to where you started. So your mental starting point for the next deployment is not quite as stable and every time you go over, the traumatic effect of the war has a greater impact on you.

"Defence says the impact of this war won't be as bad because they're doing lots of things to try to identify troops with problems, which is well and good. But war is war, trauma is trauma, and in my opinion we are going to have the tsunami that people talk about." Defence says international research on the effects of multiple deployments is inconclusive. But predicting who is likely to develop problems in the future is a complex and difficult task, with many veterans showing few signs on their return.

David Forbes, director of the Australian Centre for Posttraumatic Mental Health, says recent research has led to a rethink on late-onset PTSD. "Previously there was a view that delayed PTSD was just symptoms that had been there all along and had gradually increased and hadn't been recognised yet," he says.

"There is clearer evidence now about delayed PTSD where the person doesn't exhibit many difficulties in the aftermath of these events, but there's a precipitant or an event that triggers these events later on, such as another trauma or loss."

Forbes says the military's culture of strong social networks can actually contain a soldier's trauma for many years, meaning PTSD can be triggered by their decision to leave the armed forces for a less structured civilian life.

Defence points to the findings of the 2010 ADF Mental Health Prevalence and Wellbeing study, which shows personnel who have never been deployed are just as likely to have PTSD as those who have been sent abroad. "These findings support the argument that it is not the number or length of deployments, but the type of experience on deployment, in particular exposure to trauma or combat, that is the risk factor," a Defence spokesman says.

While the community largely remains oblivious to how many veterans are suffering from PTSD and have little contact with them, the director of the Australian War Memorial and former defence minister, Brendan Nelson, sees a constant stream. "It's very common for me upon any day to be walking along the cloister towards where the Afghanistan panel is and to see a couple of young men with short-cropped hair, wrap-around sunglasses, standing there with tears streaming down," he says.

Nelson says the War Memorial has become an unofficial place of pilgrimage for many returning young veterans, a stop on their journey as they attempt to piece their lives in Australia back together. His encounters with damaged soldiers have convinced him of the need to tell the story of Australia's involvement in Afghanistan and the Middle East as soon as possible. "Looking back on the Vietnam experience, I suspect if the War Memorial had been able to tell the story of Vietnam sooner, more deeply, then possibly some of those men might not have suffered quite so much as they have."

Chris May is one of those whose pilgrimage led him to the Australian War Memorial. Deployed to Afghanistan at the age of 19, it was the realisation of a dream to fight for his country. But before he had hit his late 20s, the war had broken the young Victorian, leaving him damaged both physically and psychologically, unemployed and unsure what to do with the rest of his life.

It began on August 22, 2011, when the phones and internet went dead in Tarin Kowt. All the soldiers on base at the time knew what that meant - bad news. Really bad news.

When an Australian is killed in action the chain of command immediately shuts down all non-essential communications to buy the military precious time to contact the family back home and break the terrible news to them before it leaks out of the base.

So when the telephone and internet suddenly stopped working that day, a sense of dread came over Chris May. "We all knew it meant there'd been a death, we all got brought in together and it was kind of like an unlucky lottery; everyone was kind of biting their lips and holding on to the hope that it wasn't one of their friends," he says.

As the name of Private Matthew Lambert was read aloud, a group of soldiers from the combat unit burst into tears. For May the nauseating wave of adrenalin and the racing in his chest subsided as the name of a stranger was read out.

"You kind of feel sick and feel really sorry for them, but at the same time you're letting out a sigh of relief it wasn't one of your close mates."

It wasn't until one of Lambert's friends showed May a photo of his fallen mate that the reality came crashing down. May realised he had briefly met him just weeks earlier while commanding his Bushmaster through an area where Lambert's unit was patrolling. May had been called to pick up a dehydrated group of diggers. Sharing a can of Coke with the exhausted soldier, May and Lambert began reminiscing about their lives back home in Australia, and the things they were looking forward to doing on their return. "Only knowing him for a very short time and not getting a chance to meet him again was pretty hard. If I could go back and have my chance again I might have asked him a bit more about his family." It was a hard blow for May, but worse was to come. During a later patrol, his vehicle approached a narrow point - an obvious place for a hidden roadside bomb.

The convoy stopped, and the engineers on board jumped out and began scanning the road on foot with metal detectors. May, positioned in the gunner's turret at the top of the vehicle, snapped off a couple of photos while he waited.

After an hour of searching, the engineers turned around, gave May the thumbs up, and he began to manoeuvre the vehicle across the culvert. As his wheel hit the pressure plate of an undetected bomb, it triggered a massive explosion that lifted the front of the 12-ton vehicle into the air, tossing the unrestrained May around inside the vehicle's metal interior.

"This is where I slammed my head against the floor of the vehicle," he says, as he picks up the still dusty Kevlar helmet on the living room sideboard and fingers a long, deep groove in its side. "They wanted me to give this back, but there was no way I wasn't going to hold onto this."

The rehabilitation from the compressed spine and the brain injury sustained in the attack took many months, leaving May with severe shakes, a bad stutter and unable to clearly piece his thoughts together. But it was the mental trauma that eventually convinced him he could no longer continue in the job he had spent his youth dreaming of doing.

Lying in the field hospital in Tarin Kowt after being evacuated by helicopter, a colleague delivered a few of his personal items, including his camera. "I was going through my camera and I realised I had actually taken a photo just before the incident. In the photo, one of the engineers is stepping over the approximate location of the pressure plate and another engineer is standing roughly in the location of the actual main charge."

Racked by guilt and feelings of having let his mates down by not completing his mission, May became overwhelmed with a sense of failure. He also had to deal with the grief the engineers felt at allowing him to drive over the undetected explosive. On returning to Australia he found himself adrift, no longer comfortable around friends and family at home, and feeling like he had abandoned his mates in Afghanistan, but unable to face returning to the place that had nearly taken his life. Offered the option of attending a soldier recovery centre near his old base in Townsville, the sight of other soldiers driving past in the Bushmasters he used to command became too much to bear.

"That just made me feel like I wasn't part of the team any more," he says. "I was so close, but I was so far away at the same time. That kind of exacerbated the whole issue of me feeling worthless."

A few weeks after our interview, May drops by to deliver some photos from his time in Afghanistan. As we flick through the files on his laptop, I ask him whether he thinks the Australian community is prepared for the number of soldiers coming back psychologically scarred by the war. "It's a different world when you come back," he shrugs. "You see everyone getting hyped up over reality TV or the State of Origin. People don't really appreciate the bigger problems of the world. In 12 months everyone will have forgotten about Afghanistan, and what then? All the guys know that's what's going to happen. Things will go back to the way they were before, and people will forget that we were ever there."

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