Holden, 38, said that the music mogul will be spending his Christmas break in Barbados with ex-girlfriends Sinitta, Jackie St Claire and Terri Seymour.
"He makes me laugh, taking his exes to Barbados. Puh-lease. One giving him a pedicure, one a manicure and one a massage. I really don't think he’ll ever settle down," she said.
"He goes off them so quick, it's better he doesn't. He is one beast that simply can't be tamed. He has women throwing themselves at him, women who adore him. It's better that he does stay single."
Cowell has now set his sights on Transformers actress Megan Fox, Holden revealed in the Sunday Mirror, adding: "He’ll probably try to date her. He's heard she fancies him and he's loving it big time. He doesn't like just tapping one girl out. He likes a few."
Filming for the next series of Britain's Got Talent begins in February.