I've seen it happen once, and I completely understood it.
Dude was a straight up asshole towards his wife. I knew her from way back inna day 'cause we dated briefly and caught up with her when we were working in the same office building around the end of '98. He lost his ability to walk driving drunk; he hit a utility pole doing over 70 on a residential street. Got ejected through the windshield and all that. She took care of him for years but he basically became more and more disrespectful towards her, constantly belittling her no matter what she's done for him. She told me the nigga couldn't piss or shit on his own so they had a nurse during the day while she worked and she would do it at night and on weekends. Dude was always talking shit about her out on how she was carrying his ass to the toilet and all that. He had to take laxatives and enemas just so he could shit and on occasion would shit on himself, so she had to clean him and the nigga would blame her for it even happening. This was the early days of Ebay, so dude would go out to Big Lots or thrift stores and buy shit for low and sell it online and keep a lil money flowing through the crib, but he framed it to his peoples and the oldest son like he was the one making all the money for the family and doing everything that she was actually doing. She said dude stayed making disrespectful comments towards her, constantly dogging her out like she was stupid, and was always complaining about her to his family.
Eventually she got fed up with being treated like shit, packed up the two youngest and bounced. Left the oldest to take care of his ass.
Everybody has a breaking point.