If he takes every opportunity to berate those people for any small infraction, then it won't be long before the behavior carries over to you. Likewise, pay attention to how he treats and talks about his family members - those who are supposed to be near and dear should be treated at least with respect. The same goes for you - if you notice your man making disparaging remarks about you, then following them up by telling you not to have such thin skin or saying "just kidding," he probably isn't kidding. Undermining you with sarcasm is a similar warning sign - don't fall victim to his perceived wittiness. Being in love shouldn't mean withstanding emotional or physical abuse, so if you feel like those red flags are flying, then it's time to end it before it's too late.