What should I do?😢

Okay so my grandma & I have always had a really close relationship. But ever since I got pregnant, she has been calling me names.. (Fat, chubby, obese) also always making nasty faces at me saying ew. She says it in a joking way but it still hurts my feelings . I've gone from 149 -206 since becoming pregnant & I'm only 36 weeks. I feel like she says any & everything to make me feel bad. It's even starting to make my mom a little mad since my 2 year old sister is now copying my grandma calling me obese & she knows it hurts my feelings because I've told her about it.   I've told my grandma before that it hurts but I try to stay away from the Subject because I almost cry every time she says anything to me. Am I over reacting? Should I just try to joke about it with her? What would you do?  It really hurts my feelings & I'm sick of it. ( i see her almost everyday, so there's really no way of avoiding it.)