He says he's anxious to start a new life, free of secrets and shame but he won't be out of the spotlight.
He wants to pursue a career as a TV interviewer and may one day enter politics.
Ian Thorpe hopes by going public, he will help others deal with the same issues.
Correspondent: Simon Santow
Speakers: Ian Thorpe, Olympic swimming champion; Michael Parkinson, TV interviewer; Deirdre Anderson, sports psychologist
SIMON SANTOW: Ian Thorpe, the swimmer, seemingly had it all - records in the pool, Olympic medals, and marketability, but the media and the public wanted more.
Until last night when the private life became very public.
IAN THORPE: I'm comfortable saying I am a gay man and I don't want young people to feel the same way that I did. You can grow up, you can be comfortable and you can be gay.
SIMON SANTOW: In an interview with the 10 Network, Ian Thorpe told Michael Parkinson he'd lied about his sexuality for years.
Even though he thought it was none of anyone's business, he'd felt he had to lie to protect himself.
All the while, he says he was trying to discover who he was and what he wanted.
IAN THORPE: I was concerned about the reaction from my family, my friends and I'm pleased to say that in telling them - especially my parents, you know they told me that they love me and they support me. And for young people out there, know that that's usually what the answer is.
MICHAEL PARKINSON: Do you think your parents were shocked by the revelation or do you think that they had- particularly your mum might have, sort of...?
IAN THORPE: They were shocked.
MICHAEL PARKINSON: They were shocked, were they?
IAN THORPE: Yeah, my mum literally said she was shocked.
MICHAEL PARKINSON: Really, really?
IAN THORPE: Yes.
MICHAEL PARKINSON: And your close friends, similarly, too, did they say to you maybe, we'd known that all along?
IAN THORPE: No, you know my friends were a little bit more like, okay... You know, fair enough. They said, you know, we had some suspicions. You know, they were
they were great, and I needed my friends first, I told them first.
SIMON SANTOW: Thorpe says even through his battles with injury and depression, he concealed his sexuality from his psychiatrist and from his friends and family.
IAN THORPE: I think that I've held
this is such a weight and there's so much pain in this and the discussion, you know that I... I had anger around this because I felt like I shouldn't have been asked about it. I wouldn't have lived a very different life but I could have been proud of the fact that, yes, I'm out.
SIMON SANTOW: Sports psychologist Deirdre Anderson has worked closely with Ian Thorpe for the best part of a decade.
DEIRDRE ANDERSON: What we don't always understand is that when you're involved in sport at such a young age, you almost skip over a lot of those life skills that we all take for granted.
And so for Ian he had to really go back and explore himself and who he was and what his moral compass was all about and what his values was all about and really redefine him, you know outside the water.
SIMON SANTOW: She says he may be a resilient athlete but outside the pool he can be vulnerable.
DEIRDRE ANDERSON: It's a really, really difficult thing when you keep pushing away the one thing that's compromising the sort of values that you have as a person. And I know he's worked really hard to try and understand what those values are, and I think he mentioned in the interview that honesty and integrity were two critical things.
And if you can't be honest and have a level of integrity about yourself, then the rest of the life that you're living is a facade.
SIMON SANTOW: What did you make of it when he said that he had been held back or damaged by being asked at such a young age, at the age of 16, whether he was gay?
DEIRDRE ANDERSON: He's obviously may not have ever put that ever put that into a phrase such as 'gay' but he obviously understood that he was feeling a bit different about the life that he was living but he hadn't put a label to it.
And I think for someone like Ian - and there's a lot of people like that - they hate labels. Pretty rude and almost disrespectful and quite dangerous thing to expose a young person to and it's- and I don't just mean asking someone if they're gay but just any personal question that is inappropriate publicly. And I think someone's sexual life or someone's personal life at that age is... I don't know what response they were expecting to get.
SIMON SANTOW: Ian Thorpe says his new life starts now and he hopes that will include a career asking the questions, rather than answering them.
He wants a long term partner, and to start a family.
Before that he'll be poolside, not in the water but commentating at this month's Commonwealth Games in Glasgow.