"Glee's" Dianna Agron didn't exactly sing a wistful ballad following her split from actor Alex Pettyfer after nearly a year together.
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Since moving out of the L.A. home she and the "I Am Number Four" star shared about two weeks ago, Agron, 24, "is staying at a hotel under an alias" a source reveals in the new Us Weekly, out Wednesday.
Why the secrecy? Pettyfer, 20, has been "a psycho loose cannon" in the aftermath of the split, another insider says.
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On Feb. 18, according to an eyewitness, he got into a heated confrontation at a West Hollywood club with actor Sebastian Stan — furiously accusing the "Black Swan" star of hooking up with Agron.
"Dianna is terrified of [Alex]," a pal explains, adding that he "absolutely lost it" and threatened Agron during a vicious phone chat. (Pettyfer's rep tells Us he made no threats.)
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To read much more about the ugly breakup, pick up the new Us Weekly, out Wednesday.