Blue's Antony Costa said his I'm A Celebrity appearance 'saved him' after the band called it a day in 2005 and he was left 'sitting at home'.
He said he struggled with what to do after the band — who shot to fame with hit 'All Rise' in 2001 — went their separate ways, with the record company and his bandmates not answering his calls because they were in meetings or busy with solo projects.
Costa told Kate Thornton on White Wine Question Time he had put 'all his life' into the band and though he wouldn't say he had gone into a depression, he did say he was 'lost' from July 2005 after the band announced a break.
"I thought, I've got to do something with my life," he said. "And the jungle, I'm A Celebrity, saved me.
"It saved me because it gave me a thing of showing what I can do, being the personality that I've got, the cheeky chappy."
WATCH: Duncan James & Antony Costa on reuniting as Blue, their greatest hits and misses, and life lessons learned along the way
He remembered driving to the TV studios and a radio presenter reading through the list of contestants on the reality TV show, which that year included Atomic Kitten's Jenny Frost and Emmerdale actor Sheree Murphy and was ultimately won by Carol Thatcher, daughter of the former PM.
Costa said the DJ called him a 'boy band has-been' — something he says he has 'never forgotten' and disagrees with because he had only been out of the band for around five months at that point.
Thornton added: "It's never a nice thing to call anybody, at any point in their life."
Saying his time in the jungle, on the show's fifth series, gave him 'a new lease of life', Costa said it opened up opportunities for him to work in his 'first love' and do more acting.
Though he said the money for the ITV show was 'not great' compared to what he had been earning with Blue, he stood up to his agent and said he wanted to go on the show, describing it as the 'best shop window' he could ever do.
He went on to appear in West End musicals including Blood Brothers and Save the Last Dance for Me and now says he owes his stage career to theatre and film producer Bill Kenwright.
He said to this day the band, who have reunited to tour again this year, call Costa 'Rolex' because he likes to know a schedule, will always be the first to arrive and be ready to work.
James said: "He turns up always an hour before everybody and he's ready to do his job, where a lot of us — I speak about myself — I'm a little bit more relaxed, I guess."
He added that he never wanted to be late, but in the mornings would 'forget about the time', realise his car had been waiting for him, and then get caught in traffic and turn up late.
"I put my hand up because that's really bad," James said. "And I've learned over the years you can't be like that.
"Back in the day, Ant was the ultimate professional and when everything started to disband, I think it affected him a lot worse than it did the others."
He said he thought Costa had 'the hardest lessons to learn' through the band's various breaks and reunions, and all members having been made bankrupt.
"But you've learned from it and you've become stronger because of it," he told Costa.
For his part, Costa admitted he had always been called on by the other band members to do interviews if they couldn't — or wouldn't.
He told Thornton: "I'm representing the band. Dunc might have been late, Simon couldn't be bothered to get out of bed, Lee was still clubbing at 5, 6, 7 in the morning.
"But that's just how it was, that's fine. I don't mind not doing that if I'm there to help the boys, I'm there to be part of a team."
WATCH: Duncan James & Antony Costa on which member of Blue constantly forgets the words to their songs