The rumor mill is churning with news that Demi Lovato and on-again, off-again boyfriend Wilmer Valderrama are off again after Demi tweeted some cryptic advice to fans recently.

“The smartest thing a woman can ever learn, is to never need a man,” read one tweet. Couple that with an insider’s confirmation to Us Weekly that the two “are no longer hooking up” and looks as though Demi and Wilmer have officially called it quits.

Wilmer has developed a reputation as something of a Hollywood predator by getting involved with a succession of teenage starlets (including a pre-meltdown Lindsay Lohan) and dumping them when they try for a serious relationship. He’s been harshly criticized for his involvement with Demi, as the actress has been in and out of rehab for emotional issues, and Wilmer refused to publicly acknowledge their relationship.

Well, Ms. Lovato can console herself with the knowledge that she’s not the only Demi to be dumped by a former That 70s Show star.

(Photos: WENN)