Advice needed.. my Boyfriend's mother called me his X's name.

My boyfriend and I been dating for almost 4 years we go to family dinners every Sunday, go on trips we see her all the time last Sunday she called me his X's name 3 times. It really pissed me off. The first time she said it I just pretended like I didn't hear the second time i said what then she said oh yeah sorry then the he last time she said it I told her please call me my name. It hurts that she doesnt seem to care.