Jack Nicholson says his legendary libido is languishing -- and that he now prefers sleeping alone.

The Hollywood legend, 65, made the remarkable confession to Newsweek in a wide-ranging interview where he shattered his lady-killer reputation.

"I'm a different guy here in my 60s. I don't have the same libido," Nicholson told the magazine.

"It used to be that I didn't think I could go to sleep if I wasn't involved in some kind of amorous contact or another.

"Well, I spend a lot of time sleeping alone these days. That's different. And very liberating."

The star of such classic movies as Five Easy Pieces, Chinatown and One Flew Over the Cuckoo's Nest now worries that he prefers a solitary sleep.

"It wasn't until the last few years that I became completely comfortable with it," the three-time Oscar-winning actor said.

"You know, my fear is that I'm beginning to prefer it."

Nicholson's latest comedy -- About Schmidt -- is generating the kind of buzz that suggests the role will earn him his 12th Oscar nomination.

The latest in his long line of beauties is stick-thin star Lara Flynn Boyle, but the gregarious actor wouldn't shed any light on their relationship.

He did admit he wasn't the guy to give romantic advice.

"This is the one thing my close friends never come to me for advice about," Nicholson said. "They think I'm too goofy about women. In love with love."

Along with the womanizing, Nicholson also concedes his party-hearty days have come to an end.

"There are a lot of crazy nitwit things I can't do any longer," he said.

"I can't work on a movie for 12, 14 hours a day, then go out and burn the streets down to the ground all night and get wild.

"I don't have the energy for it."

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