Spew. I'm sorry you are struggling so much. I would algal stiffest finding out what she means by "red zone" and maybe asking her about her attitudes and reactions to self harm. For me is a large and looming problem almost all the time, so that one of the first things I ask about. I ask hypothetically and depending on their reaction, I will disclose or not disclose details.
Perhaps after establishing what red zone is to her, and what it means, you guys could go over a safety plan if you intend to stay seeing her?
Is not that things can't be fixed, you just have to find the right person to help you through things.