Treat Their Guests With Kindness and Respect
To be clear: you shouldn't feel obligated to put up with anyone pushing your boundaries. But when your roommate invites guests over, you should try to treat them with kindness and respect — even if you don't like them. You don't have to be buddies with your roommate's buddies, but getting along with people is part of life. And if you want your roommate to treat your guests with kindness and respect, you should do the same for them.