Personally it sounds like your a wonderful mom.
I think when a person dies, all of a sudden all the anger for that person disappears and that person is put on a pedestal even if they never really deserved it, unfortunately she has redirected that anger to you. No doubt when it’s your turn she will have so much guilt, and that’s when it’s your turn for the pedestal!.
Just know in yourself that you have done your best . She is blaming you for her shortcoming’s, she’s acting entitled.
She a lucky to have you, and doesn’t deserve you ♥️
I hope she comes to her senses!!