"It's a combination of all of this that put him into depression.
He went on: "He just wants some space totally away from boxing, which is understandable."
Fury defeated Klitschko for the WBA and WBO titles 11 months ago. But despite his successes his career has been mired by controversy including accusations of homophobia after outbursts from the star. Meanwhile, last month he pulled out of a rematch with Klitschko after being deemed "medically unfit".
The British Boxing Board of Control is meeting on Wednesday to discuss withdrawing his licence.
In a wideranging interview with Rolling Stone Fury talked about the personal issues, including his drug use and suicidal thoughts.
"I'm a manic depressive. I just hope someone kills me before I kill myself," he told the magazine. "I am seeking help but they can't do nothing for me ... I've been pushed to the brink. I can't take no more. I'm in a hospital at the moment. I'm seeing psychiatrists. They say I've got a version of bipolar. I'm a manic depressive. All from what they've done to me. All this s**t through boxing, through taking titles, through writing me off."
Peter Fury told the BBC he was uncertain what to believe in the interview and claimed some parts of it were incorrect.
"He said in his interview that he hadn't been training at all, he hadn't done any training for five months, well that's totally untrue."
Fury had been training at his boxing gym in Bolton, Lancashire and at a local members' sports club, his uncle said. Although he said the boxer was like "an empty shell" during training.