Hi liberty,
I've been following your story and I really feel for you.
I'm not trying to toot my own horn, but to me, your question seems connected to my post about kidnapping & the Stockholm Syndrome: Why do we not leave the N? and, on the other hand, what are the consequences when do do leave the N?
Here, you've decided to leave the N, but she's trying to pull you back with veiled threats of suicide.
Do you call her bluff, or not? I don't know.
If you contact her, have you given in? On the other hand, if you contact her and reaffirm your original letter, maybe she'll get the point and maybe that could be a "win" for you.
I'm just trying to think this out.
What if you emailed her and told her that since she never took your letter seriously, you decided to do a "no contact" but, that if she agrees to discuss your letter in a meaningful way, you'll listen? But then, you'd have to listen to her, yuck!
What about having a therapist referee a session with her?
It's a really difficult decision.
dazed