Expert on Bristol and Levi: 'Very Immature Young People'Breaking up isn't hard to do in Hollywood. Since so many celebrity relationships dissolve, it almost doesn't seem newsworthy that 19-year-old Bristol Palin and her on-again, off-again fiance Levi Johnston are off again.

Sarah Palin's daughter has a 19-month-old son, Tripp, with Johnston. But Levi's rumored obsession with the limelight -- he famously did a photo shoot for Playgirl magazine -- and the reportedly strained relations between him and the Palin family led to the couple's first downfall.

Is it any surprise then that less than three weeks after their sudden Us Weekly engagement announcement, they were kaput yet again? Bristol told PEOPLE on Tuesday that "it's over, I broke up with him," and says she "got played" by a fame-hungry Johnston.

went to relationship expert Isadora Alman, who writes the nationally syndicated advice column 'Ask Isadora,' to find out why lasting love is so hard to find in the limelight -- and to figure out what the deal is with Bristol and Levi.