Mother-in-Law HELL

I”m expecting twins in Feb. and my MIL has said things that have made my “pre-maternal” alarms goes off, these are my first children, and I already feel an overwhelming instinct to protect my girls from this harpee. She lives with my DH and I because she has no where to go. But my DH knows his priorities are with me and our twins. Even though she think this makes him a “traitor” but I know this is a desperate attempt to cling on to her son,franklly it does not work. When I got my first ultrasounds at 7 weeks (as we all knwo they looked like little squiggles.) She called them “my babies” and kept them in her purse for a week, the only reason she gave them back to me is because my DH made her give them back to him. When I heard her say my babies, I told her that these are my kids not hers, and then the airbag gave me a guiltrip says but these are her grandkids(of course the guiltrip did not work). A few months later, everytime she showed her friends around the house, she would say “this is where the babies will sleep” I got vexed when I heard that. This made me immediatly go to my DH and almost me yelling at him for the crap his mother would say. He reasssured me that he will make sure that she will know her place. I told him, if he does not I will. She has even made comments about what cribs they will be in and hoe their hair will be. The funny thing is , as soon as she see me get pissed of and say to her, “This is between me and your son” She says “Well it’s your decision, and then act all bitchy ” I’ve told my DH to explain to his mother in their native tongue (I tried to give her the benefit of the doubt due to speaking such bad English.) I know that my DH will stand behind me, this is not the issue. But this stuff has literally messed with my sleep. Should keep doing what I’m doing, act like a bitch when she does this crap?