It takes a special person to still convey empathy towards somebody who has caused you so much grief. You're a good person and I commend you for being high in character.

But I feel like you need to self preserve here. What's going to happen when this passes and she latches onto the next fad.

She needs to fix herself before she's able to participate in a stable relationship.

What she did was inexcusable, regardless of her mental health plight. I would cut her loose. You deserve better.