End of the Line for Joe Jonas and Ashley Greene

Wonderwall, Thursday, March 17, 2011, 9:17am (PDT)

By Kat Giantis

After less than a year of paparazzi-documented coziness, Joe Jonas and Ashley Greene are dunzo. Multiple outlets are reporting that the middle Jonas brother, 21, and the "Twilight" starlet, 24, have gone their separate ways, and their reps confirm the split to People.

"It was mutual and amicable," an insider tells the New York Post, which cites the old standby of busy work schedules as the reason for the split.

The relationship, which kicked off last summer, reportedly ended a few weeks ago (the pair was last photographed together in late February). But not everyone believes the decision to call it quits was entirely a joint one.

"Joe wasn't that into it," a source shrugs to Us, which says the romance hit a rough patch last month.

"They broke up shortly before her [Feb. 21] birthday," says a source, "then got back together."

That might explain why Joe was photographed keeping his purity ring-free hands stiffly at his side as Greene threw her arms around him during her birthday bash at Pure nightclub in Las Vegas.

Still, she gushed to People magazine about the vintage Chanel charm bracelet he gave her to mark the occasion: "I absolutely love it because he knows what I like."

Jonas also talked up how simpatico they were in the April issue of Details, noting that the relationship "feels good."

"I think what works about it is she really puts my feelings first," he shared. "She understands my busy schedule. She'll fly out to my shows -- she's been to places in South America that I can't even pronounce."

RELATED: More of Joe in Details

Jonas also racked up the frequent-flier miles for Greene, twice joining her in Baton Rouge while she was on location for "Breaking Dawn."

If Ashley is upset by the bust-up, she wasn't letting on while hanging in New York this week. The Post says she hit hot spot Avenue with several pals, including Kings of Leon rocker Jared Followill.

RELATED: Ashley on Joe: 'He's sweet and really funny'

As for Joe, whose famous exes include Taylor Swift (ditched in a 27 second phone call that later spawned the hit song "Forever & Always"), Camilla Belle and Demi Lovato, the breakup should provide some additional emotional fodder for him to mine for his forthcoming solo record.

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