Adam Levine is "heartbroken" following his split with his swimsuit model girlfriend.

The Maroon 5 frontman and Anne Vyalitsyna have called it quits after two years of dating. Anne reportedly pulled the plug on the relationship while she was in New York and he was in Los Angeles.

"[He] was blindsided," a friend of Adam's told Us Weekly. "Adam's heartbroken. He wasn't even fully sure they were really broken up."

The Sports Illustrated model announced the breakup earlier this month. The 26-year-old issued a statement saying the pair will remain on good terms despite the split.

"It was a cheap shot," the insider adds. "Anne didn't want it to look like he broke up with her."

It is understood Adam, 33, never predicted his girlfriend would end their relationship. Friends of the pair, on the other hand, saw it from a mile away.

"Anne said he didn't pay her enough attention," a friend of the model's said.

"Levine wasn't planning to propose anytime soon. As a woman, you get to a point where you want to get married. Adam wasn't ready to take that step."

The pair were targeted by rumours their relationship was on the rocks before Anne confirmed the split. In January, there were reports that the couple had parted ways following a huge argument. At the time it was claimed Anne had ditched the singer because she didn't think he was treating her well. Adam had slammed the reports saying they were "100 per cent not true".

However she later revealed it was over.

"Adam and I have decided to separate in an amicable and supportive manner," she told People.

"We still love and respect each other as friends. I wish him all the best."

Adam and Anne met at a Sports Illustrated party in 2010, where Maroon 5 were performing.