Nightmare mother. Need help!!

I apologize in advance for the length of this post.

Background: My mother has always been very bad about respecting people’s space, following their wishes and just really terrible social skills in general. The world is about her and everyone she cater to her whim. I truly believe, as does most of my family and multiple therapists that my mom has munchausen by proxy. When I was a teenager I had horrible sinus infections and chronic migraines. She would take me to every specialist under the sun and then wouldn’t let me tell them my own symptoms. She would do all the talking and often report symptoms that didn’t exist. If I tried to correct her, I was yelled at and told to shut up. It got better when I got to college mostly because my dad got legitimately sick (massive health problems as a result of being shot in Vietnam) so she was able to turn her focus on taking care of him for the next ten years. Unfortunately he passed away in November and my mom is understandably struggling. She was his full time caretaker for ten years and now she doesn’t know what to do with herself. Unfortunately for me it means now the focus has shifted back to me and as a result, my pregnancy.

She visited this past weekend and the entire time was pure hell. We went shopping since my work pants were getting too tight. Should be simple enough- just buy pants. Turned into a huge affair. The entire time she kept telling me how big I’m going to get and not to buy xyz because I am going to get huge. Then she kept bringing me shirts and stuff that are a tent for two on me and says I should get it anyways because I will get huge so I will grow into it. Keep in mind these are winter sweatshirts and stuff. I’m due in August!! I’m not going to be that big by April!!!! I told her to back off and stop saying I was going to get huge because it made me feel like I was going to gain fifty pounds and be a whale. She of course tried to explain it away but then still said I would be huge so get the giant tent sweaters. 😑 Unfortunately it only got worse.

All weekend she kept shoving her face into my stomach and talking to the baby. She would also keep touching me all the time- my belly, my leg, my arm, my head etc. in public she would rub my belly without asking like I am a magic lamp or something. We have not publicly announced the pregnancy yet which she knows and yet she told any person who came near us that I was pregnant and she will be a Grandma for the fourth time (all while rubbing my belly). When I told her I was extremely uncomfortable with her rubbing my stomach all the time and shoving her face in my belly so close she would make my stomach hot with her breath she called me a brat. According to her she has Grandma rights and can talk to her grandbaby whenever she wants. I told her I have a personal bubble and I don’t like it violated. In her eyes the bubble doesn’t apply to her because she is my mom. She said my brother and my dad talked to her belly when she was pregnant with me so it’s fine if she talks to my belly regardless of my feelings. She also never shoved her face in my sister in laws stomach when she was pregnant (because she didn’t like it either) but she said it didn’t matter what I felt about it since I am her daughter, not daughter in law, the rule doesn’t apply to her. Again- Grandma rights in her eyes. 🤯 she needed up hanging up on me when I continued to stand my ground and set the limitation.

So yeah... in summary I’m a brat for setting limits and stating what I am and am not comfortable with regarding my own body.

I don’t know how to handle this with her because she is refusing to respect my boundaries. I know she will not respect my boundaries and rules when the kid is here (watched her get into WW3 with my brother over each of his kids) and I don’t know what to do. I know she is a lot to deal with but she is still my mom but I also have to protect my kid. She got mad when I told her the baby won’t sleep with the blanket she will knit until they are older. She yelled at me and said I did and I was just fine. I reminded her of SIDS and she said that’s stupid and it isn’t a real thing. Tons of babies survived blankets for years. Didn’t matter that I wasn’t willing to risk my child suffocating. I just don’t know what to do. I set boundaries and she just openly defies them and goes straight to insulting me. Any advice is appreciated. Sorry for being so long winded!