Alloy.com

For some reason love and Hollywood couples go together like water and oil. Sure, if you shake it up, they'll mix, and they might even stay chummy for a nano second. But after a minute of downtime, they split apart! So what's the deal? Love experts and authors of several relationship books (available on www.chroniclebooks.com), Em and Lo spill the deets on Hollywood's hottest couples and ex-couples. Read on to find out what really went wrong with stars like Kristin Cavallari and Brody Jenner and maybe you'll uncover some classic dating mistakes you're guilty of! By Elisa Kim.

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