“Hands off my man!” That’s the message Nicole Richie has sent out to her former, BFF Lindsay Lohan, after seeing this shot of the I Know Who Killed Me star trying to pick up her beau, Joel Madden.

Lohan, who is notorious for flirting and hooking up with men already in relationships, was seen partying with Good Charlotte frontman Madden during one of his recent ‘wild nights’ out in L.A.

According to a source, new mother Richie is furious with her hard-partying man, and it isn’t just because of his antics with LiLo. Not only was Madden sleazing it up with Lindsay, he was also “partying to his heart’s content with strippers in Florida,” while Richie stayed home to look after their young daughter, Harlow.

“Nicole is not happy with her man,” a close friend revealed. “Joel’s running around acting like he’s still single.”

The same weekend that Joel was partying hard, the rocker denied he was planning on marrying Nicole. Trouble in paradise, perhaps?

[Source]