Not the jerk. Don't give her any money. Remind her she wished you dead, never born. Then tell her you absolutely are dead to her and she to you. If you hadn't been born she wouldn't have money from you and she should live as if she never had you. She is a terrible person and an even worse "mom". I'm glad you're doing well for yourself.
Awesome you learned how to cook. As a woman who hates cooking, it was awesome having an ex boyfriend who liked cooking and my current boyfriend loves cooking. So has definitely worked out for me. There's nothing wrong with it. You're family is being extremely hypocritical. They are also gaslighting you (playing down your feelings and calling it a joke). Gaslighting is a form of abuse. Keep your food in your room. Don't cook for them unless/until they apologize and stop doing it. Also, save as much as possible to get out of there asap.