Paris Hilton Is Single

Paris Hilton and Benji Madden have called it quits after nine months of dating, a rep for Hilton confirmed.

The reason for the split?

"Benji was overprotective and controlling. He doesn't get along with any of her friends," the source tells Us. "Friends thought Paris had changed since being with Benji and she wants to be herself again."

The couple stayed faithful to each other, stresses the source. Hilton was spotted with her ex, shipping heir Stavros Niarchos, in Miami over the weekend, while Madden, 29, hung in NYC with his bro, Joel (beau of Hilton's best friend, Nicole Richie).

"Nothing went on between Paris and Stav in Miami," the source tells Us. "She was there for a girls weekend with her BFFs.

"Benji really respected her," the source adds. "They will be friends forever."

Hilton and Madden first made their relationship public on February 21, smooching at Hollywood hot spot Villa.

They grew serious quickly. Both were spotted wearing rings with each other's initials, and Madden called Hilton "wife material."

In April, Hilton gushed on her MySpace blog: "I've never felt so happy and in love, [Benji] is such an amazing guy and life has never been better!"