She is already a problem 🤦🏽‍♀️

So at the beginning of my relationship with my fiancé me and his mother were extremely close. I spent the night over her house, we went shopping together, etc. Then I got her involved with my family’s personal issues because I’m in the middle of trying to get my you her sister out of an abusive household and my fiancé’s mother knows a lot about law. She got in contact with my dad, who lied about the situation entirely to cover his ass. And then on top of all that, my fiancé was in route to go to rehab (he has a drinking problem). To top all that off, when I would tell his mom how bad he needed help, he would lie to her and tell her I was lying so that his mom wouldn’t be “mad” at him. We had been living with his mom and her wife for about 6 months, and when he got home from rehab we moved all of our stuff out. I just started my first cycle of clomoid, and during the move I discovered that all fertility pills were missing. Everything else was intact except for those, so that automatic set off a red flag. His mother had went into my belongings and stollen my fertility medications! We messaged her to get them back and she tried to guilt trip my fiancé. I am seriously concerned that she is going to be a problem when I have our baby and I dont think I’m up for the challenge. It’s really frustrating.