Dougie Poynter has said his McFly co-stars were almost like father figures to him in his younger years as his own dad had walked out on his family.
Poynter, 31, said he still did not know how to feel about the abandonment of his father, which came just before he joined the pop rock band.
The musician, McFly’s bassist and youngest member, joined the band at the age of 15, two weeks after his father walked out on him, his mother and his sister.
Poynter told Mariella Frostrup’s Books To Live By podcast that it was “the worst thing to happen to me” before “the best thing”, joining the band.
He said: “I came home from school one day and mum was crying and was like, ‘dad’s gone’. I still to this day don’t really know how I feel about it because I don’t know how big a role he played in my life.
“It was always about my mum. My mum was incredible.”
Poynter said he had not seen or heard from his father since that day, but had found the support he needed in his band-mates Harry Judd, Tom Fletcher and Danny Jones.
He said: “I’ve got other father figures, the guys in McFly became proper older brothers and taught me how to shave and sneak into clubs and how to drink – all the really useful stuff and I really think that helped gel McFly, for me anyway.”
Poynter also told how he went on a path of destruction while in the group – known for hits including Five Colours In Her Hair and Star Girl – before he realised he needed help.
He said: “I think people in bands or in the industry get into that side, one, because you haven’t really got a proper job and two, because you overthink a lot about what people are really buying into – is it really you or is it this character that you’ve created.”
He said he “couldn’t stop” and that he was partying so much he felt “terrible” all the time, and realised he needed to “clean” himself up.
“I got really fortunate with something that snowballed and before I knew it, the secret was out, the band knew, then management knew and there was no messing around,” he said.
“They rescheduled the tour and the next thing I remember was waking up in rehab and completely freaking out and trying to leave.”
The Books to Live By … With Mariella Frostrup podcast is available now on BBC Sounds.