psycho MIL

Venting, comments welcomed, especially if you're in a similar situation. My husband and I have been married for about a year and a half and I've never been close to my MIL, which is weird because with previous exes I had an amazing relationship with their moms. I get along with my husbands step mom great though thankfully! His mom is psycho & degrading to the point he has blocked her number and I recently told him he should reach out to her after not speaking to her for a few months but just to keep her in her place & not allow the disrespect to come back. She has me blocked on Facebook yet somehow screenshot our pregnancy announcement and posted it to her own Facebook. Purely for the attention for herself announcing she will be a grandma. (My mom has her on fb, that's how I saw it, and they don't have a relationship with each other either) anyway, his mothers whole side of the family is this way. We have had falling outs with that side of the family because they would over step boundaries multiple times even causing drama on our wedding day. Now his mom talks to my husband about the baby and I am not planning on inviting her to my baby shower. Just the step mom. My concern with reaching out to her again was her prying her way back in just to try to play "grandma" and act like all this drama hasn't been happening. I don't want to expose my son to that kind of behavior or ever have her try to put things into his head. It may sound horrible but I'm not sure when I will be comfortable having her around the baby. And never alone!!!! She keeps telling my husband she's buying the baby all this stuff and I don't even care. I really don't want it.