I'm shocked that no one else has responded to your message. In fact, I joined Mumsnet in order to respond because at some point in her life every woman on this forum will become the target of the misogynistic toxic blame that you describe.
At the moment something similar is happening with Meghan Markle. Now I'm not a fan. I have no opinion of the woman. I never saw Suits, and had no idea who she was until she and Harry got involved. From what I've read I can find nothing to criticise.
What has shocked and infuriated me hasn't been her family's abusive behaviour, but the willingness of so many ordinary people to believe their outrageous claims and excessive demands. Her father, step-sister, and step-brother have been caught telling lie after lie, even contradicting previous claims they have made. Despite this, many thousands of people continue to believe everything they say, and then attack the poor woman for not taking care of her father. The women who were sending in the comments were more hostile and demanding than the men.
Thomas Markle is 74, ambulatory, and not suffering from dementia, apparently. He has a declared a monthly income of $4,200. Why should a man who has a history of gambling, spending thousands on lottery tickets, and losing money by investing in get-rich-quick schemes expect his daughter to bail him out?
The man can take care of himself. If he chooses not to, he has no one to blame but himself when his health fails.
I'm disgusted that women still are expected to cave in to bullying, bullying that is excused by people who witter on about 'forgiveness' excusing bad behaviour with claims that the person made a 'mistake'.
I find myself wondering how many of the people who criticise Ariana Grande and Meghan Markle will go on to scapegoat their own sisters and daughters.