Oh and if that doesn't really help much.
You don't actually need personal experience of being bullied to understand that being mean hurts. Aside from the fact children as young as 5 understand this fact as a basic..aside from that, she has eyes and can actually see the effect of her words. Unless she is actual genuine psychopath, she will see your response and generate some empathy. She just justifies her behaviour or doesn't care that it hurts you.
We would all like to believe that if someone truly understood their effect on us then they couldn't possibly treat us this way. It's a much harder truth to swallow to acknowledge they are fully aware of their impact and may enjoy the power they feel in belittling or otherwise hurting us. They may feel justified. It's to correct you somehow.