Sorry Kit, it seems your T is out of her depth if you want support with self-harm. Also, you shouldn't have to educate her at your expense. it should be up to her to educate herself.

And frankly, merely reading books will not be enough to help her support you effectively regarding self-harm. Yes, she might gain some understanding but that is not enough to help you re formulating a plan, safety strategy etc. There also needs to be experience and specific training in order to be effective. It can be dangerous for a T who is not experienced to counsel a client who needs more specialised care or support. They can do more harm than good.

When working with clients in crisis or in distress, having good intentions (e.g. I want to help my client) is simply not enough, there needs to be proper training and expertise in place too.