3. He's too into you.
According to Cosmopolitan, guys are protective of their emotions.
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"So, if we start to feel like we're getting into a situation where we'll be destroyed if you dump us," admits one male expert, "we might launch a preemptive strike and yank the plug first." Sound phony? Perhaps men are the sensitive creatures we so desperately want them to be. Perhaps they, too, worry about falling hard for a woman who seems too good to be true. If you are that woman, you should spend five seconds congratulating yourself for being too perfect and then promptly move on to a man who isn't such a baby.
4. You're too maternal/not maternal enough.
Speaking of babies, men don't melt at the sight of a small child quite in the same way some women do. If a man thinks you're treating him too much like a baby or have housekeeping and other assorted domestic desires too much on your mind, he's likely to akin you to his mother and not his lover. On the other hand, if you reject anything that has to do with feeding, grooming or taking care of him, he may think that a long-term relationship with you will be like living in a bachelor pad without the Playboy subscription. A man may love a woman who can cook but also wants a woman who is willing to get down and dirty, minus the Mr. Clean, if you know what we mean. The balance between domestic goddess and sexual diva is difficult to obtain. Tilt the scales just so, and he's likely to trash the relationship.
5. His best friend saw you first.
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Men don't gossip the same way that women do. If your boyfriend finds out one of his pals had a crush on you or worse, hooked up with you before he called first dibs, he will forfeit the game without putting up a fight. It's fine if his friends think you're hot, occasional jealousy is even welcomed, but sloppy seconds or stealing someone else's girl is a total man rule that is never meant to be broken. It's easier to date a woman that your friend can only dream about seeing naked than suffer with the knowledge that his best friend saw you first.