Wow, I'm not even sure where to begin :D
"Mom" has plenty of issues, "son" is right behind her, but the woman in question, I can't help but wonder - didn't she get any clues before marrying a man who would become very angry with her over "disrespecting his mom"?
I'm glad she stood up and protected what I believe are firm boundaries. She gave her options that she refused. MIL didn't just want a room she can lock, she wanted their room.