Bones you are completely correct in your Mother In Law rant.
My cousin, who is now in his mid-50, got married 30 years ago and his mother told him that his wife was out to ruin his life when she got pregnant shortly after their wedding. For almost 15 years she saw very little of that Gbaby or the second one. They went to counseling and the counselor said a husband should always choose his wife over MIL, unless a married couple defends their autonomy as a couple, their marriage wont be strong enough to survive. Its been said the first obstacle in marriage is getting over what other people think about the relationship. When they told her to stay away, she showed up unannounced at their home numerous times causing trouble so they got a restraining order against her.
My mother is the same, she ruined/broke up my brothers first marriage, which was not a good marriage to start with - she was a pregnant girlfriend who became a wife and she had a lot of problems of her own, magnified in a bad marriage with cruel people around you who want you to fail. My brother is now remarried to a woman who is essentially untouchable in terms of criticism (nice girl, nice family, MA in Education, self sufficient, kind, great with her kids and his previous ones, well liked in the community, church-going) but MIL can find something - mostly that she is a granola eating liberal hippie who wears birkenstocks and no makeup. Anyway, this one can see my mother for what she is, maybe it helps that her mother is PHD in psychology, but will have none of the non-sense that my mother put out.
My mother also confronted my brother three days after his last (third) baby was born in 2007 and wanted -no sorry angrily demanded - an explanation about why he is not giving the baby a name from her familys side. He has three sons, and all have a first or middle name from my Dads side of the family (along with the surname, last name of my Dad for obvious reasons). She denied the confrontation when I asked her about it, but it happened for sure, my brother, his wife and her inlaws claim it did happen on more than one occaision.
That said, there are many times when I see that people in the family have no idea how cruel and malicious my mother is. There are some days when I want to hurl insults at other family members but I dont because I know how it feels and I know its wrong. When I imagine hurling insults at people and being malicious like my mother is, I wait to be called on it, so I can respond with "Have a problem with that? Take it up with my Mother, thats what she taught me" Nobody seems to be aware of how abusive she is and just once it would be nice to have people be on the receiving end of her type of cruelty and get some validation. This will never happen of course, but I can dream....