Don't wanna go to Easter dinner

Ok so this may come across as kinda rude but let me explain. My husband's aunt is making dinner for Easter and invited us to come. My husband has to work and my SIL and BIL won't be there either. So it would just be me, his aunt and uncle and his parents. I love his family and have done stuff with them without my husband before, but now that I'm pregnant, they treat me like a delicate flower and make comments about how much I eat. My FIL has pissed me off twice about his comments and not being able to keep stuff to himself and I just don't want to deal with him.if my husband or SIL and BIL were there it would deflect some of this away from me but if it's just me, I have no deflection and it's awkward now. His aunt keeps texting me about it and I keep saying I'll have to see what my parents are doing, which is nothing. his aunt runs into my mom in town a lot and she would know if I lie about plans with them. I don't know how to get out of this dinner without coming across as rude. help!!!