Nicole Richie Won't Let Benji Madden Enjoy the Single Life

Is Nicole Richie getting a little too possessive...of her boyfriend's brother? Spywitnesses tell Page Six that the starlet keeps blocking Benji Madden from flirting with other girls since his recent breakup with her sometimes-BFF Paris Hilton--and as a result, he can't enjoy his newly minted bachelor status.

The situation went overboard at a recent party for Good Charlotte's new Greatest Remixes album, where Benji and brother Joel Madden celebrated while Nicole kept a too-close eye on the scene:

"Benji was approached by dozens of ladies. Girls were trying to flirt with him...but Nicole kept getting in the way." The source noted that Richie "stopped every girl trying to take a photo of him," and even "dragged him by the arm" away from a busty blond.

Props to Nicole for looking out for her girlfriend, but wasn't the breakup between Paris and Benji mutual? Seeing as the heiress goes through boyfriends like handbags, she probably won't mind her latest ex flirting with other girls. Maybe it's best for Nicole to follow a new mantra: to each his own!