I guess I’m the asshole

I’ve been with my husband for 10 years. 8 years out of those 10 I was skinny. When I got on birth control 2 years ago I started to gain a lot of weight. This excited my mother in law because now she could harass me about my weight. First it started off and small comments. “What size are you now? A large?” Or she would buy me clothes that were obviously too big for me. I would shrug it off even though it hurt my feelings because i just KNEW it would make bigger problems. I wanted to keep the peace. I recently posted about how on Friday she straight up called me fat. I’m 6 months pregnant now and I am already struggling with the fact that my body is changing. I was wearing a dress and she just says “wow the baby looks FAT in that dress and so do you! Well both of you do!” I told my husband and he was inferiorated. Of course he told me enough was enough and he told her to never comment on my looks again. I was pregnant not fat. She then sends me a long text message saying how dare I think she called me fat. It was a compliment to my belly and she loves me and would never hurt my feelings and she was sorry. I forgave her. Fast forward to yesterday we went to his parents house to pick up my car (my father in law had been working on it). We say hi to her and she completely ignores us and doesn’t look at us. Fine, we go outside to talk to my FIL about the car and he ALSO doesn’t look at me? We then here her get up from the patio table, throw the chair and slam the door and she goes inside. We leave and take my car and I tell my husband that this exactly why I never wanted to say anything before but she crossed a line and now I seem like the bad guy. Am I blindsided now and can’t see if I’m really the asshole here? I always knew she would be like this but

My FIL is seriously the sweetest person and I don’t understand why he wouldn’t even look at me. Either way now I don’t even want to go around there because I don’t need this energy at 6 months pregnant.