It’s no secret that Selena Gomez has been going through a tough time since her split from Justin Bieber, but she embarrassed herself when she allegedly threw a fit and cried at Taylor Swift's star-studded birthday party on Dec. 12.

Partygoers like Beyonce, Jay Z, Justin Timberlake and Nick Jonas enjoyed beer, pizza and sushi, while Selena got super emotional over her ex-boyfriend on the upper terrace of Taylor’s Tribeca apartment, according to Us Weekly.

“She shouted, ‘No one understands me! My boyfriend doesn’t even understand me,” a source told Us Weekly, adding that partygoers, including Sam Smith “just stared [at her].”

While Selena’s outburst seems like a total buzzkill, the rest of the party had a “total blast,” a source also told the magazine.

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Taylor’s party also brought together Olivia Culpo, Chrissy Teigen, Kelly Osbourne, Emma Roberts, Shawn Mendes, Charli XCX, HAIM, Karlie Kloss, Ansel Elgort, and more.

Taylor posted an Instagram photo from the bash and captioned it with: “So this is being 25….. #WHAT #bestbirthdayEVER.”

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