Uh oh! Turns out, Selena Gomez's relationship with Justin Bieber isn't the only things that's had its ups and downs for the ""Come and Get It" star. Sources tell Us Weekly that Gomez's on-again, off-again romance with the "Heartbreaker" singer is now causing a rift between her and best friend Taylor Swift.
"Taylor hates him. She thinks Selena makes a mistake every time she reconciles with him," a source tells Us Weekly. "Bieber has really come between the girls."
In fact, when press asked Swift, 23, about Bieber at the Billboard Music Awards in May, the "I Knew You Were Trouble" singer declined to comment. "Can we have another question?" she replied. Gomez, 21, and Bieber, 19, were later caught kissing backstage.
Swift may not be fond of the young star, but the is feeling is mutual. "He complains Taylor's always telling Selena she can do better," a Bieber insider tells Us.
Though Swift didn't ring in Gomez's big 2-1 birthday bash with Bieber and the rest of her friends in Malibu on Saturday, July 27, Swift tweeted days earlier on July 22 that Gomez was "the closest thing I've ever had to a sister." A rep for the "Everything Has Changed" singer also reassures that "Selena and Taylor are great friends who talk almost daily."