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Dianna Agron isn't having much luck in love this year.

The "Glee" actress, 25, is no longer dating "Captain America: The First Avenger" star Sebastian Stan, 28, two sources tell Us Weekly. The couple first began dating in late May, just months after Agron split with Alex Pettyfer, her co-star in "I Am Number Four."

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One insider says Agron and Stan broke up because she was "super jealous" of any woman who appeared too close to the former "Gossip Girl" actor.

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"She was always worried that he was cheating on her while he was away filming," the source tells Us. "But he never would!"

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According to the New York Post's Page Six, their bicoastal romance became too much for Agron to bear. "Long-distance wasn't working," a source told the newspaper. "Dianna's coming to New York for Christmas with her mom, so they might rekindle the flame."

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