"He was deeply worried that he was going to disappoint his fans. He even said something that made me briefly think he was suicidal. He said he thought he’d die before doing the London concerts. He said he was worried that he was going to end up like Elvis. He was always comparing himself to Elvis, but there was something in his tone that made me think that he wanted to die, he was tired of life. He gave up. His voice and dance moves weren’t there any more. I think maybe he wanted to die rather than embarrass himself on stage."
Much more at the link.