Politicians often "self destruct" in scandal rather than admit they want to resign, MP Mark Oaten has said.
The MP said he was now spending more time with his family
But he said he was "happier now than I have been for ages", since being forced to quit the Liberal Democrat front bench over a liaison with a rent boy.
In a film to be aired on BBC Two's Newsnight, the Winchester MP said he did not enjoy the pressures of being a politician but that it was like a drug.
"The politician doesn't know when to stop, they can't get off," he said.
'Not brave enough'
In the film to be broadcast on Tuesday, Mr Oaten interviewed a psychiatrist, a journalist and another MP caught up in a scandal, to find out why politicians like him "come off the rails".
He said former Education Secretary Estelle Morris was one of the few people who admitted she did not want to do the job any more and resigned.
"The rest of us, it seems, carry on until we almost do press some kind of self-destruct button and then the decision is forced on us, and that's almost easier than having to make the decision yourself," he said.
He said he felt a "sense of relief" after his own scandal was exposed.
Front-line politics felt like a "drug addiction" because he knew it was not good for him but was unable to stop, he said.
The MP, whose wife Belinda has spoken out about the impact the affair had on her, said he had "fallen out of love" with Westminster life before the story broke.
"There wasn't a day that went by when I didn't think 'actually, I don't want to do this' but I wasn't brave enough to give up, but because of what happened to me, that decision's been taken from me.
He added: "I'm happier now than I have been for ages (because of) the sense of not having that 24-hour-a-day pressure."
He said he was spending more time with his family and children.
"But the way it happened has obviously been disastrous for everybody," he added.
Watch the film on Newsnight on Tuesday 23 May, on BBC Two at 2230 BST.