When you or someone you know is in a relationship where one or the other experiences extreme emotional highs and lows on pretty much a dialy basis.
Derek's girlfriend is freaking out agian, he can't come tonight he is riding the bi polar coaster.
His ex rode the bi polar coaster all the way to crazyville
His ex rode the bi polar coaster all the way to crazyville
by Ze-Berger October 28, 2009
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