My brother just broke up with his girlfriend for the second time in eight months. They had been together for two and a half years, and she became pretty discontent when she finished college and my brother entered law school because all his time and attention weren’t revolving around her. In January, she staged this bizarre, soap-opera-esque situation to make my brother jealous, and then broke up with him when he reacted predictably. (This is not speculation—she admitted to it.) After the breakup, my brother became a mess of a person—sobbing all the time and talking about her to anyone and everyone. At the risk of sounding insensitive, he was unbearable. Then, against the advice of my family, he started talking to her again and they got back together. The second breakup came after he snooped and found out she had been texting her ex-boyfriend. She was...