9 Relationship Taboos That Will Drop Your Boyfriend's Trust in You to Zero

4. Bad-mouthing him behind his back with your girlfriends

“If she’s got a problem, she can say it to my face.” If he finds out you’ve been talking about him behind his back to your girlfriends, he might never be able to trust you again. Even if you make your friends promise not to tell, chances are that he’ll still find out some way or another. As the saying goes, “If you can’t say anything nice, don’t say anything at all.”