Mil help plus possible separation anxiety !?

So I will just start off by saying that me and my mil never got along, she was incredibly controlling with my SO and never liked me for literally no reason. She is also emotionally unstable. No

We moved in with her when I was 37 weeks pregnant because she begged us to while we were getting our house updated so she could bond with baby, I hated the idea but agreed. Just to give you and idea of the relationship she has with her son, she actually found out I was pregnant at 36 weeks because he knew she would try to control everything.

During my pregnancy and stay with her she questioned everything I ate, tried to check my blood pressure every day, would buy things for the baby like his crib even though I already had it and had specifically asked her not to. She questioned everything I did and everything I chose for the baby, the list goes on but I’m sure you get it. We had specifically asked for no visitors at the hospital and of course she visits without permission not once but twice! And while in labor she rewashes all of his clothes and reorganizes everything for him. Ever since we came home with him she’s been a complete nightmare, turning the heat so high he had a 100 degree temp and we had to take him to the hospital to make sure he’s ok, she’s always accusing us of abusing him because apparently we don’t dress him warm enough in 70 degree weather. She criticizes everything I do and tells my SO she feels bad for our son.

I knew she would be like this so I’ve never let her hold him or see him for more than 3 minutes and he’s 6 weeks old, she will sanitize and wash and reorganize all of his stuff the second we leave the house and it seems like she’s clinging onto anything that has to do with him.

Recently my SO has started to feel bad that she hasn’t had time with the baby so he’s brought him into her room yesterday and today, she held him and starts singing to him whine dancing around the room, I genuinely want to punch her and take my baby away. The whole time she’s saying “his diaper needs changed” or “he’s not being fed enough!” Or “he’s obviously freezing, out some socks on him”.

We are moving into our house in a month but how do I survive until then? She’s treated both me and my SO so bad that I just can’t stand her being around my son. I get super anxious when she even talks to him.