Stop calling me fat, I'm pregnant..

Every time I go around my family members someone (usually my mother) calls me fat. They comment on how I'm "carrying" it's not even like they say it as a joke. I know a lot of people jokingly say, "Are you sure it's not twins?" etc but these comments are not jokes. It really hurts my feelings. I've asked them to stop but it just gets worse. I'm 6 months pregnant and constantly crying. It's to the point where I'm about to cut my family off completely.. They have no respect for others feelings. Idk what to do. I'm sick of feeling fat because of these comments. I just want to enjoy my pregnancy. 😢