"I am someone who has everything people dream of, but there was always something missing.
"When you get to a point when you rationalise the process of suicide, you can’t sleep at all at night and when you feel it’s actually a viable option, that’s when you know you need more help.
"I experienced that. I hit rock bottom, then found another layer below that.
"It’s not a chapter I wanted to publish, but I’m glad I have been able to. It's been a bit cathartic."
The 30-year-old also discussed his relationship with the media, his thoughts on American rival Michael Phelps, his second coming to swimming, failure to make the London Olympics and the constant innuendo over his sexuality.