4. Britney Spears and Kevin Federline

After marrying and then divorcing her high school friend Jason Alexander, Britney Spears began dating a back-up dancer named Kevin Federline. Many people opposed Spears dating Federline because he was a bad boy and wasn't financially stable. It was reported that Spears bought her own ring when they got engaged. Their personal and sexual life was documented on their reality show Britney & Kevin: Chaotic. Some critics called the show "the trashiest show on television" at the time. Their relationship soon ended after Britney had enough of K-Fed's behavior after the birth of their son.