I'm not going to say impossible, but being "friends" with your BPDex isn't likely to work, and if it does, it will be because you have incredible boundary skills to back it up.
I've seen a reasonable number of people try it here, and cannot think of one case where the push/pull dynamic went away. Assuming the "friendship" lasts long enough to go through a few cycles, it is going to happen. You will be pulled toward intimacy (at least emotionally) beyond what normal friends have if things go well. You will be painted black and ignored/shut out.
Yes, I see this potential. I have confidence that I can enforce boundaries where needed. I do know she can be a great friend but given the circumstances I fear I would just be used when she needs something from me. I would be
her "friend", it wouldn't be mutual in the sense she could be a friend to me. The fact she has shown no concern for my feelings post trash bin or offered an apology (sincere or not) does not inspire confidence in me that she can be my friend.
My personal fear is while I really do miss the friendship I might find it difficult to keep my own emotions where they would need to be, assuming I can get past all these painful emotions that surround the very thought of her right now. I cannot escape the fact that I do love her in spite of everything and probably always will. That doesn't mean I can overlook what she has done though, but eventually it will all fade to the background and hopefully with that fading will come indifference.
You aren't in a place where that is safe for you today. You may never even want it
These are both true and I still feel quite conflicted. Until I can resolve the conflict there will be no reply.