The Simple Split: Paris Hilton and Nicole Richie

They practically birthed the 2000s reality boom on The Simple Life, but the billionaire besties hit a cataclysmic wall in 2005 amidst rumors that Nicole had screened Paris's infamous private tape -One Night In Paris - at an industry party. Paris didn't hold back when confirming their inner circle was permanently broken, releasing an official press statement on 20 April 2005 that read: "It's no big secret that Nicole and I are no longer friends. Nicole knows what she did, and that's all I'm ever going to say about it."