Knowing that she's clearly very, very troubled, is it worth taking anything she says seriously? It would be different if someone called you something, like lazy, AND it was true. But she seems to say stuff just to hurt you. And you let it hurt.

My mother accused me of refusing to teach her to drive when I was sixteen. I didn't even have a driver's license until I was nineteen. People can say all sorts of hurtful things. It's best to let those things roll off of you like water off a duck. Even if what they say is true, it still doesn't matter, because you have to look at the whose mouth the words are coming out of.

Honestly, if you were in a restaurant and you saw someone just like you getting berated by someone just like her, would you take it personally? If not, then try to apply the same thing here. This isn't about you and her. It's about her. So let it be about her. Act like you witnessed this, rather than you participated in this. It seems to me there's no real lesson in this for you, except don't take her seriously. It sounds like she needs help that she will never get.