Being the parliamentary pariah is no fun at all.
Even Senator Mal Colston, a man whose appetites - for food, frequent-flyer points and freebies - was matched only by his complete absence of shame, discovered that there's nowhere quite so lonely as Parliament House when no one wants to know you.
I had a little to do with Colston's eventual undoing and so, in the interests of balance and accuracy, I had cause to speak to him repeatedly about the damning evidence that was coming my way.
Sex was Colston's undoing.
OK. I'll give you a minute to pick yourselves up off the floor. Yes, sex - and Colston.
Specifically, a letter that the good senator's wife, Dawn, wrote to Bob Hawke's special minister of state, Mick Young, in 1983. In that letter a cheated and angry Dawn said her husband had misused Commonwealth spousal travel warrants issued in her name so his lover (I'll abstain from naming her) could travel with him on parliamentary business.
The letter included other allegations about her husband's quite criminally ingenious abuse of Commonwealth entitlements.
Young ordered his department to investigate Colston. The senator was ordered to repay about $10,000 and the department recommended the case be passed to the Australian Federal Police. Labor never pursued that advice.
Dawn, of course, had sent the letter when she was fuming with big Mal. They eventually buried the hatchet, but Queensland Labor kept the correspondence for a rainy day.
That day came in 1997, six months after Colston quit Labor and - with Coalition support - became deputy Senate president.
After I received the correspondence between Young, the Colstons and the department, I rang Dawn first. She refused to discuss it. This was not a denial.
What surprised me most, however, when I rang Colston, was his insistence that a) the situation in the correspondence had never happened; b) that if it had he couldn't possibly remember because it was so long ago; and c) the paperwork in my possession must have been a Labor fabrication. It was all, he said, a conspiracy to which I was clearly a party.
This, as it turned out, was a great insight into the pathology of the man. Mrs Colston's correspondence about ''the other woman'' was just the beginning of Mal's troubles. Soon evidence of his widespread rorting of travel allowances and other Commonwealth entitlements swamped the front pages. Colston denied it all.
Eventually, he was charged, John Howard realised a line had been crossed (it was easy to see) and the Coalition had to forgo his vote - but not before using it to secure the part sale of Telstra.
What astonished me about Colston was the passionate, pathological veracity of his denials in the face of overwhelming evidence - and from a man who'd never been passionate about very much except rorting.
Soon, no Coalition MP would be seen with him. Labor MPs muttered vitriolic abuse when they passed him in the corridor. Eventually, Colston took to having all his meals in his Parliament House office and when he sat on the crossbench only the avuncular Brian Harradine would inquire of his welfare and state of mind.
Colston died of cancer in 2003.
I bumped into one MP who'd pursued Colston since his defection from Labor in August 1996. Of Colston, the MP said he'd ''had a kill''. It was the most chilling insight I'd ever had into the ugly brutality of politics.
Comparisons with the present are, of course, unavoidable.
The venal Colston made it easy for Labor to hate him because he quit to take a Coalition inducement.
But the MP Craig Thomson, the subject of tawdry and very serious allegations relating to his time as a union official, enjoyed the backing of Labor - which relies on his support in the House of Representatives - until well after it became untenable.
Labor has suspended his party membership. But, having preselected him well after the allegations first surfaced, it has a duty of care in relation to his welfare. Recent episodes in Australian public life herald the need for caution as Thomson, a man under enormous pressure, prepares to explain himself to Parliament.
Shame is a potent weapon in Parliament House.
Some, like Colston, seem unsusceptible to it.
Parliament can be a lonely place. Mal Colston proved that.