Jesse McCartney's Water Babe

Jesse McCartney made waves frolicking with gorgeous Jasmine Waltz — an aspiring actress best known for her spring fling with Ryan Seacrest — on a Malibu beach.

"Jesse's had trouble committing to one girl," an insider tells Star of the singer, 22, who's dated Katie Cassidy and Hayden Panettiere. "But he's wild about Jasmine. It's been a few months, and it's going really well."

Jesse proudly escorted Jasmine, 27, to Comic-Con in San Diego in July, and they were seen dining happily à deux the same month.

"He's even written love songs about her," adds the insider. "He's become the perfect boyfriend!"

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