I think this is genuinely a case of a woman whose been severely abused and neglected her whole life, unfortunately finally completely snapping in a very illogical way due to her mental health being so deteriorated from the prolonged trauma that her rationality went out the window.

OOPs MIL was brutally abused for years,and sold as property to a man who didn’t love her.her MIL tried to kill herself the day after she did it & was clearly genuinely suicidal enough after the incident that psychiatric assessors made her stay in the hospital for a month. Anyone who didn’t genuinely feel horrible wouldn’t do that, just because people are sometimes bad at expressing apologies doesn’t mean they don’t feel guilty.

Also her FIL is absolutely right they should feel like scummy POS’s for allowing their lives to be eased by the profits of abuse and then shitting all over the abuse victims character for one terrible incident (that would admittedly be devastating for anyone to experience) which the MIL has apologized for and proven she’s gotten better.

If I was MIL i too would have been incensed at everyone around me ignoring clear signs of an abusive marriage for years, so they could reap financial benefits like new cars and fancy weddings.