"The fifth rule after a breakup—never kiss your ex. Even if you’re so drunk you can’t stand." In fact, I broke many rules already when I asked my ex—who had the worst temper in the world—to play along at my sister’s wedding. I convinced him to act as my boyfriend for two weeks, because I was still afraid to tell my mom that we’d broken up. And that led to huge trouble. The only thing left was not to neglect the most important one: "Never sleep with your ex. Even if you really want to."