people generally don't like my bf..

so I'm like one of the most laid back person you've ever will meet.. and my boyfriend is truly a great person at heart and I honestly don't let the little dumb things he does get to me. but other people don't like him a lot when he's drinking.. idk what it is but I can tell when we get around other people we are new to they just aren't fond of him when he's drinking.. which is the only time he's around people because when he's sober he's to shy to actually talk to people. Idk how to help him.. I know obviously it would be for him to stop drinking but that's not gonna happen..