Labour MP Simon Danczuk has spoken of the personal cost of his battle to expose child sex abuse, saying it left him depressed and helped wreck his marriage.
The backbencher said he was receiving psychiatric treatment and would be stepping back from his campaigning.
The member for Rochdale, whose bitter split from wife Karen has been played out in the media, previously investigated allegations against ex-MP Cyril Smith and pushed for action over other historical abuse claims.
But he told BBC Radio 4's The World At One that his experience over the last year had left him with suicidal thoughts and drinking too much.
"I would say I have been suffering from depression to the point where I have decided to seek help for that," Mr Danczuk said.
"I was getting angry at stuff that I shouldn't be getting angry at, fairly mundane things.
"I was getting aggressive - not violently aggressive - but just getting angry about things.
"Perhaps drinking a bit too much, a full bottle of wine of an evening, and especially on Fridays when I would hear a lot and meet with a number of the victims. At times suicidal thoughts as well.
"It's not been really bad, but thinking that it is quite a lonely place."
Mr Danczuk said he went to the doctor after the election and was referred to a psychiatrist, who gave him "permission" to step back from the campaign.
The MP, who first entered the Commons in 2010, said he was "in no doubt" that the problems affected his marriage.
"I think it took its toll on our marriage, there is no doubt about that," he said.
"I was struggling to sleep at night. Some nights I might get four hours sleep, so you're waking up and you're not in the best of moods.
"On a practical level, Karen would say why don't we not talk about this tonight, can we have a night off talking about child sexual abuse.
"Because I would be coming home some nights wanting to download some of what I had heard.
"Not everyone wants to listen to it, do they, quite understandably.
"No doubt that it has had an impact."
Asked about the effect of MPs' work on their mental health, he said parliament was a "lonely place" and there was an expectation to be "tough".
"I do not think that's such a virtue in this day and age," he added.