Long story short my MIL contributed heavily to me having prenatal depression and anxiety 9 years ago when I was having my DD. Me and DH (then bf) lived with her. She wouldn't let me sign on or claim any benefits but had next to no money herself. I ended up sobbing one night as she wouldn't let me have 14p to buy paracetamol for a really bad pregnancy migraine. I ended up leaving when my father found out how bad things had got. (DH was at college miles away and she always saved it up for when he was gone). MIL then took over multiple times once DD was born and would invite herself over to sleep at our flat to "help out". When I'd question this I'd be told it was my PND and I needed help.
Years later I started putting an end to the weekly sleepovers and visits and DH started to see things from my perspective. I felt stronger and could say no.
My GIL became very ill and needed a full time carer so we seen much less of MIL (although still had weekly visits).
Problem is now DH grandad has died and MIL is desperate to start staying over at our flat again. I have a DS now who she doesn't like because "she's had 3 boys and is done with them" and the more she's around the more anxious and upset I become.
I do not want this woman to stay here because I know once this starts she will never leave.
What would you do in this situation? 