In the early 2000s, Paris Hilton and Nicole Richie were the A-list BFF's of the moment. The pair famously co-starred in their own reality show "The Simple Life" together. Hilton and Richie called it quits in 2005.
"Nicole knows what she did, and that's all I'm ever going to say about it,'' Paris told People at the time.
Paris moved on to a then-unknown Kim Kardashian, toting the future reality mogul along with her to red carpet events and clubs. Once Kim skyrocketed up the Hollywood ladder, the friendship ended.
Paris even went on to take jabs at Kim's biggest asset: her butt. In 2009, she referred to it in a radio interview as "cottage cheese in a trash bag".
Demi Lovato recently put the final nail in the coffin of her former friendship with fellow pop-star Miley Cyrus. Lovato called in "The TJ Show" in Boston to promote her new skincare line and was forced to address the falling out with ex-bff Miley Cyrus when a fan chimed in with a question.
"Um...yeah... that, um... we're, we're like, we're acquaintances," Lovato said. It was awkward.
Sometimes breaking up with your friends in Hollywood can be worse than breaking up with your boyfriend.
Demi Lovato is all too familiar with BFF breakups. The singer used to be attached at the hip to fellow Disney star Selena Gomez. The pair met as little girls on "Barney and Friends," but over the past few years have grown apart. According to rumors, the rift was over Taylor Lautner.
While Demi turned to Miley, Selena turned to Taylor Swift. But that relationship wasn't all sunshine and rainbows, either.
Earlier this year, T-Swift allegedly booted her bestie after Gomez rekindled her relationship with Justin Bieber. Good news though -- this week, Swift was spotted crying during Gomez's emotional performance at the AMA's, so it looks like they might be friends again ... for now.
Check out celebs and their furry BFFs:
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