Mark Oaten has expressed his "regret" at being involved in a sex scandal but pledged to continue as a Lib Dem MP.
Mr Oaten quit as the Lib Dems' home affairs spokesman
In his first newspaper interview since revelations of an affair with a male prostitute, father-of-two Mr Oaten said his family was "most important" to him.
The former party leadership hopeful, 41, told the Hampshire Chronicle he felt "sorry for the things I've done wrong" but had received much support.
Mr Oaten, MP for Winchester, resigned as home affairs spokesman last month.
The News of the World revealed he had a relationship with a 23-year-old male prostitute.
The scandal came shortly after Lib Dem leader Charles Kennedy admitted he had had a drink problem and resigned from his post.
Mr Oaten told the Hampshire Chronicle: "I think my priority in the next week is my family - my wife Belinda and the children - and really to focus very much on them, and also Winchester, my constituency."
He added that "I do have regrets and apologise about what has appeared in the media since and I'm very sorry for the things I've done wrong so I've got regrets, of course, about that."
Mr Oaten said: "If I've learnt nothing else in the last 10 days, it's that my personal life and my family life is the most important thing and I regret not getting the balance right over the last four years as I should have from time to time."
Last week Simon Hughes, the party's president and leadership contender, said Mr Oaten still had a future in Parliament.
Mr Hughes said: "He's stood down from the front bench - that is the price he's paid. I don't think it follows that you stand down as an MP.
"If you look back in history, many people have given up office but they have continued to serve their constituents very well."
Mr Hughes said he hoped people would understand and forgive Mr Oaten.
Chris Huhne and Sir Menzies Campbell are the other MPs competing to be the party's new leader.