Peter Fury, who is also the boxer's trainer, blamed a "witch hunt" for his condition, complaining that sustained criticism has "done a lot of damage" to the 28-year-old.
Fury had been originally due to defend his titles against Klitschko in July but pulled out with an ankle injury. The fight was rescheduled for next month but is now on hold again following last week's surprise cancellation, which was blamed on an unspecified medical condition.
"He is seeking help and there will be a statement issued, probably on Tuesday," Peter Fury said in an interview with iFL TV.
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"When he won the world title he said to me: 'I came back, I picked up the paper, I expected to be celebrated.' Straight away, he said, the hate campaign started.
"He was complaining about it a lot but said: 'OK, we've got to accept it, I've won the world title and this is how I'm treated. On many occasions he's asked: ‘What's it for? Because if I'm not being credited for the work I’ve done and what I've achieved, why am I bothering'?"
Fury, who has spoken about suffering from depression, is a controversial figure, whose conservative views, particularly on gay rights and abortion, have been heavily criticised.
The gay rights campaigner Peter Tatchell called his views "deranged and offensive".
Fury has faced other problems, as well. Earlier this year, the boxer was charged with a doping offence by UK Anti-Doping after a urine sample allegedly showed traces of the banned stimulant nandrolone.
Fury insisted he is innocent and is suing Britain's anti-doping and boxing authorities.
Peter Fury said: "There's a lot to be answered for. It's very disappointing for me because we've got a super talent here and he's been driven underground with it, almost to the point that he's at breaking point.
"He's at an all time low. I think he's always been a little up and down in the past, a bit volatile, always has been, but never like this. He just sees it as a complete witch hunt, and why bother? Everyone needs to look at what they're doing, they're doing a lot of damage to him. He's a nice human being, Tyson, no matter what people say. He’s a gentleman to everyone and this is how he gets treated."
However, Peter Fury said he expects his nephew to be back in the ring. "100 percent (he will be back)," he said. "I don't think it is anything severe in terms of long-term effects but he needs a bit of time out to take the pressure off, needs some medical assistance, and I think he’ll be OK."
(Reporting by Neil Robinson; Editing by Toby Davis)
