Pregnant engaged in law issues help

Hello I am recently engaged to my father of my children we have a 8 year old girl and baby boy due in nov, I’ve been having some issues with my mother in law, she is always at my house and always goes out with us when we go out to eat or run errands it’s starting to be overwhelming and gives me some anxiety, he and I have been together 10 years and we are looking for a house great I know however he wants both my mom and his mom to move in with us and at this point because I already have issues with her I don’t want to move into a house since we all live separate now any advice on how to deal or talk to her about her self and how I feel.