Whatever self-help-scam guru or conservative politician told you that your mum has NPD, they were probably lying. And if by some miracle you were actually told this by a doctor (unlike 9/10 people who make these claims), then blaming her abusive behaviour on neurodivergence is not scientifically sound. People with mental disorders are possessed of free will. They are not monsters, or trolls, or goblins, or vampires. They don’t follow mystical rules of behaviour. They are sapient human beings possessed with the gifts of consciousness and free will. They are capable of choices.

Your mum chose to be abusive. The illness didn’t choose for her. If you want to believe a mental disorder was responsible, and not a human being, then you’re diminishing her choice to abuse you. You’re saying it wasn’t her who did it, it wasn’t her who is responsible. That’s a form of Stockholm syndrome. You’re refusing to believe the fact that a person, a human being, can have been so awful as to have chosen to do those things. You need to deny the concept of free will in order to rationalise your abuse as a form of natural, inevitable disaster. If it was a cosmic accident, an illness, a psychological inevitability, then it wasn’t cruelty, not really. That’s what you’re grasping at straws to believe, because it isn’t quite as bad as the truth. But the truth is it was cruel. A person abused you, not a mental illness. She could have chosen to be a good parent to you, even though she’s neurodivergent, and she didn’t. And that sucks, and I’m sorry that you had to experience that.