Did Selena cry about Justin at Taylor's b-day party?

Taylor Swift sure knows how to throw a party! To celebrate her recent birthday, the "Shake It Off" singer invited dozens of friends to her New York City home and made sure that there was enough pizza, sushi and fun music to make everyone happy. But while guests like Justin Timberlake, Karlie Kloss and Jay-Z and Beyonce mingled, Taylor's BFF, Selena Gomez, reportedly sulked. In an emotionally charged moment on Taylor's terrace, which overlooks the entire city of twinkling lights, sources say Sel had a breakdown. "She shouted, 'No one understands me! My boyfriend doesn't even understand me," an insider who was at the party remembers. Sel's outburst reportedly left other partygoers super confused. "Singer Sam Smith just stared at her," the insider continues. It's safe to assume that Selena was talking about her on/off relationship with Justin Bieber, and it's not the only time he's crept up in her thoughts lately. "She's getting a ton of attention from other guys" a source says. "But she's still so obsessed with Justin. It's really hard for her to move on." It can take a while for a heart to heal after a breakup, and since Sel and Justin dated for so long, we're sure she just needs a little more time.