The Ace of Spades hitmaker, 67, has been forced to take it easy since suffering a "severe haematoma" and undergoing heart surgery to have a pacemaker fitted earlier this year (13), issues which recently prompted the band to postpone its European tour until next year (14).
However, Lemmy admits the personal problems have triggered feelings of depression.
The former hellraiser, who famously boasted about sleeping with more than 1,000 women during his youth, tells the New York Times, "I just feel really down. I'll never get a job again. I'm paying for the good times, I suppose. It's a mixture of all the things I ever did - and I did plenty."
The Motorhead star, who also suffers from diabetes, has quit smoking and cut back on his heavy drinking, telling the publication, "I drink wine and that's it."
Longtime bandmate Phil Campbell admits his friend is really struggling through the health crisis.
He tells WalesOnline, "The main problem is that he's displayed such a hard persona all his life (and) it makes it difficult for him to let people in. He's like the John Wayne of rock - always wanting to soldier on and handle things on his own."