Karma/Need to vent

I'm having a hard time being sympathetic right now. So here is the situation and I know some people will have some mean things to say but I want honesty.

My brother-in-laws' mother(not my husband's mother) mentally abused them, physically abused them, including my husband when his father was married to their mother. She has caused my brother-in-laws permanent neurological damage from the things she has done to them and uses the money she gets for her autistic daughter to buy herself food and electronics. I hate this woman with a dying passion and she has never stopped. My youngest brother-in-law, now 16, has been hospitalized multiple times because of her in the past few years. Well today this woman had a stroke. I have zero sympathy for her and I feel like this is karma for ruining the lives of her children and feeling no remorse for her actions. I have no issue showing empathy for my brother's, I love them dearly, it's their mother I don't have any sympathy for. I feel like a bad person but they know no matter my feelings for her, I will be by their sides through this whole thing because I love them and that matters much more. My husband on the other hand, feels the same way about her I do. I just need to vent about this and hear what others have to say.

Thank you all for reading, I appreciate your time and words.