George Shelley is out of Union J, according to his former band mates.
But Jaymi Hensley says there's no truth in reports George left the band because the others were jealous.
Speaking to Newsbeat, he describes it as a "heartbreaking situation" but says he is determined for Union J to continue.
A spokesman for the star said earlier that it was a "mutual decision" and called the other members "jealous".
The boy band reportedly gave George him a final ultimatum in an email.
Josh Cuthbert, 23, said: "He did the jungle, he came off it and his head space was different to ours.
"Using a sporting analogy, he wanted to turn up to the big matches but not turn up to training."
He also posted this note on his Twitter feed.
It says that he wasn't able to commit to the group., external
Union J say they are now planning to replace the 22-year-old with a new fourth member in the next few weeks.
Writing on Twitter, external, Jaymi Hensley, 26, said: "I can certainly say this decision has not come from any bad feeling, jealousy or anything else of that nature.
"I will always support and be George's [friend] and [am] so happy he is being amazing and slaying what he's doing.
"[It's] just a very sad day that has been blown out of proportion."
Listen to Jaymi speak with Newsbeat's Jimmy Blake., external
A spokesman for George Shelley said: "It was a mutual decision for George to leave Union J so he could focus on his broadcasting and acting career.
"He is an utterly charming and hardworking individual - not a diva in the slightest.
"The fact of the matter is that the other members of Union J are simply jealous he has achieved the start of an exciting new career and they have not.
The contestants from last year's I'm a Celebrity won best entertainment programme at the National Television Awards
"George had agreed to be totally magnanimous towards them, but unfortunately this has not been reciprocated."
He's also tweeted to say that he was shocked to read news reports claiming he was fired.
George said the decision to go their separate ways was "mutual".
He once again said that he wanted to concentrate on broadcasting and acting., external
The spokesman said that his career now includes being a "regular part" of the Capital FM Breakfast Show, hosting the Brits Red Carpet Live and filming a part in BBC Three's Murder In Successville.
George Shelley poses in between two minions at this year's Toy Fair in London
George, who recently posted a YouTube video talking about his attraction to men and women, wasn't an original member of Union J.
The group were originally named Triple J and competed on The X Factor in 2012 - as did George Shelley.
The two acts agreed to join forces during the show after they were both kicked out before judges' houses.
Union J posted a photo of themselves without George Shelley last weekend., external
On Wednesday, George Shelley posted a photograph of himself playing the guitar on Instagram.
The caption said: "Throwback. Started writing again this week, feels good.", external
Newsbeat filmed a documentary about what happens to band members when they leave groups.
Watch After The Band., external
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