Dianna Agron has split from her boyfriend Sebastian Stan.

The Glee actress and the Gossip Girl actor - who began dating in July - have decided to call time on their relationship as they were struggling to cope with a long-distance romance. A source close to Dianna - who lives in Los Angeles, while Sebastian is based in New York - told the New York Post newspaper, "Long-distance wasn't working. Dianna's coming to New York for Christmas with her mom, so they might rekindle the flame."

Dianna's friends have also claimed the relationship can never work because she has trust issues. One pal told Us Weekly magazine, "She was always worried that he was cheating on her while he was away filming, but he never would!"

Before the split, Dianna - who used to date British hunk Alex Pettyfer - said she had never been happier. The 25-year-old beauty said, "I'm the happiest that I've ever been. Ever. High school, middle school - I've loved every part of getting older and growing, but I definitely think that this is the most I've ever felt like myself and that I'm being treated like who I feel I am."