A mental disorder afflicting teenage girls, characterized by extreme highs at the sight of Justin Bieber with marked lows or depression upon hearing of his association with Selena Gomez.
Boy: OMG, Justin Bieber is dating Selena Gomez?!

Girl: WAAAAHH! (The Snooki waahh) FML! I need a drink!

Boy: Someone has Bi-eber-Polar Disorder,

Girl: STOP MAKING FUN OF MY MEDICAL CONDITION!
by SUNRHAE February 14, 2011
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