Playing out a relationship in the limelight must be difficult, but imagine going through a break-up with the world's press watching! Don't feel too sorry for the celebs yet, because some stars get revenge on their exes by reinventing themselves after the split.
Looking hot at the Nickelodeon Kids' Choice Awards recently, Katy couldn't stop smiling. (That's what we like to see!)
Click through to see Katy Perry and other A-listers who benefitted from their break-up.