"Even though they are still in love, they felt it would be better to just be friends," an unnamed source close to the "Repo! The Genetic Opera" star told the magazine.
"Benji was overprotective and controlling. He doesn't get along with any of her friends," the source continued, sharing their thoughts on why the couple called it quits. "Friends thought Paris had changed since being with Benji, and she wants to be herself again."
Things moved fast for the couple, who made their relationship public in February. In August, Hilton confirmed in an interview with MTV News that the two had co-written a song for her upcoming album, saying their talents and sensibilities "really mixed well."
"Well, he's such a talented writer. We're in love, so we can really write well together," she said at Comic-Con in San Diego. "We're kind of on the same wavelength, the way we think."
According to Us, Hilton was spotted over the weekend canoodling with ex-boyfriend Stavros Niarchos in Miami. Their interactions reportedly remained platonic.
"Nothing went on between Paris and Stav in Miami," the magazine quoted their source as saying. "She was there for a girls weekend with her [best friends]."
Madden's twin brother, Joel, recently had a baby with his girlfriend and Hilton's friend, Nicole Richie.