This is 100% what happened to the host mom I've been au-pairing for. And to many other moms my friends have been au-pairing for.
Married out of college, 4 kids, he spent 15 years building up his career while she took care of the house and the kids. When he was earning $600k a year suddenly he started to pull away - she wasn't as pretty anymore, the kids were loud, the house was a mess... She wasn't good enough anymore. He got himself a flat. He got her me and my precedessors to help with the kids. No, they can't divorce, that would make him pay her money for the kids and he didn't like that. Every once in a while a bill would be unpaid. My weekly checks would bounce. We lived in a $1,5mil house around DC and our gas or water was turned off more than once.
Somehow he was always out of money.
By accident she learned from a friend of a friend that he was actually seeing a young lady lawyer for a few years now. It wasn't her, it wasn't lost interest. He was just a piece of shit.
Thankfully, she had family that took no shit and they stood behind her and borrowed her money for lawyers to force the divorce now that she had proof of him cheating. She's spent tens of thousands to get there while he was resisting every step of the way - because without divorce he wouldn't have to pay her alimony, he could just throw scraps whenever he wanted and still pretend to be a good dad.
She's spent tens of thousands and two years to free herself from this man, and when she could finally go to work (thank fuck she finished college) she was earning $25k a year.
She only managed to get away with the support of her parents and family. Through the au-pair grapevine I've known other families like that. Too many. Lady down the street tried to commit suicide when same happened to her - she was from Taiwan and had no support to get free. And people around scorned her for being "dramatic" - women who held on to their places with their fingertips talked shit about her, because their own husbands would never...! Right?