Sir Michael Caine says he would have been dead "long ago" had he not married Shakira Baksh.
They married in 1973 and have a daughter, Natasha, 43.
Michael Caine bares all
Actors Harvey Keitel and Michael Caine discuss their military pasts and new found friendship, while promoting their new film Youth.
The British actor had previously been married, to the actress Patricia Haines, but credits Baksh – now Lady Caine – with making him a reformed character.
The Dark Knight and Alfie actor told the Radio Times: "Without her I would have been dead long ago. I would have probably drunk myself to death. I was a bit of a piss artist when I was younger, I used to drink a bottle of vodka a day and I was smoking too, several packs a day.
"I wasn't unhappy but it was stress. You know, 'Am I going to get another picture? How am I going to do this part? How am I going to remember all those lines? I've got to get up at six in the morning and I hope the alarm works.' There was always some stressful thing.
"Meeting Shakira calmed me down."
In his biography, Caine said he first laid eyes on Shakira when she starred in an advert for Maxwell House coffee and he knew he had to meet her. He arranged for a mutual friend to phone her on his behalf and asked her out for dinner.
They were married in January 1973, in Las Vegas in a "no fuss" ceremony in the Little Chapel on the Green.
The 82-year-old added: "She's my right-hand man, my confidante. I tell her everything. I was famous when I met her, but I couldn't have got this far without her."
Caine and Haines had one daughter together, Dominique, and he now also has three grandchildren.
Promoting new film Youth earlier this month, he told The Telegraph.co.uk: "I love my wife. I have three grandchildren. I am overwhelmed with happiness every day.
"They [grandchildren] come to us. Our house has got the swimming pool and the cinema.
"I have a happy family life, which is incredibly important to me, because I regard the family as the greatest thing on earth."