Dougie Poynter says going to rehab was the "best thing" he ever did.
The McFly star admitted he was embarrassed at first about needing to seek treatment for alcohol addiction as he worried it made him a "cliche" but is now celebrating eight years of sobriety and could not be happier.
He told The Sun Online: "I've been sober for almost eight years. It has changed my life dramatically. You're a bit of a prisoner.
"The definition of insanity is repeating the same thing over and over and expecting a different outcome and that's pretty much what I was doing.
"There were so many things that I wanted to do but I couldn't do because I was trapped by addiction. So getting clean and going to rehab and going into the programme was one of the best things that I ever did. Probably single-handedly the best thing I ever did.
"I was just drunk all the time - so now I can actually hold a conversation. At first I was ashamed - not about recovery but I felt it was a bit cliche - guy in a band goes to rehab.
"If it wasn't for my bandmates I don't think I would have been able to stay sober. They were my biggest support network. To me it will never, ever be broken."
Dougie, 30, also insisted he is single, although he admitted he and his former girlfriend Ellie Goulding - who dated from 2012 to 2014 - are "best friends".
He said: "Me and Ellie are like best friends. We are both involved with WWF (World Wide Fund for Nature) and we're both doing the same thing with conservation.
"We've got a lot of mutual friends, and we were friends before we started dating. We are really, really good friends."
He added: "Right now I'm single. I'm just too busy - I just did two feature films back to back, and then I was recording and touring with my band Ink, environmental stuff with WWF, then my clothing line Polonius takes up a lot of time."
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