I think a lot of them are from a bad childhood. I also think that they lost the ability to see for themselves that what they are doing is wrong.
I know that I have the potential to be a just no. I have a short temper, I always think I am right, and I am a very possessive and jealous person. A lot of this is from my childhood.
Things were often taken away from me because Stepford didn't like them, so I have attachment issues. Same with people. I would make a friend, only to lose them because I wasn't allowed to spend time with them and they'd find another friend that could. A perfectly reasonable thing for them to do now that I look back on it, but it felt like I was being abandoned at the time.
The short temper and the always being right comes from so many years of fighting to even have a voice. No matter what when I was a kid, I was wrong. Because Stepford was always right.
Now, the thing is, I recognize this in myself. I see the potential for me to be a nightmare MIL or mom. And I will fight tooth and nail to NOT become one of them! My husband, gods love him, lets me have my way a lot. But he also does not put up with shit. If I get bitchy, he tells me. If I seem too harsh, he tells me. If I am wrong, he tells me. I told him years ago that he needs to be the leash that keeps me from going justno. Because I can twist logic to justify my view like no other. I learned it at a very young age from a master. Who probably learned it at a very young age from her mother. So he has promised to protect our children, even from me if needed.
I know this probably makes me look pretty bad, but I am at least trying, and I am honest enough with myself and my husband to realize that I have the potential to go to the darkside. A lot of these women probably didn't have that moment of realization. Their husbands don't let them know, they don't see it themselves, and by the time their kids are adults, they are so set in their ways that anyone telling them they are wrong must be manipulative or mean. Because if they were wrong, someone would have told them years ago! Their behavior is perfectly acceptable, thank you very much, and your behavior/ expectations/ beliefs are just unreasonable. (/s)
At least, that's what I think. I could be wrong, and they could just all be batshit crazy. Who knows?