I was going to say that if she has respect for you then nothing would happen between them, but then I thought well if nothing is going on with you two now then as harsh as it sounds, life goes on. Just to add in that this is why you need to be clear with the both of them and with yourself about what you actually want because every decision made will have a consequence.
That said, my instincts would be that I would expect better of any of my mates, particularly when things are still quite raw.
I suppose time will tell and you will find out soon, but it sounds like you're getting to grips with it by not feeling like being nice or pandering to her, which in the long-term if you two are not going to be an item is probably a good thing. It's also a good thing because, although I can appreciate what you've said about her issues, if she doesn't think twice about snapping at you then she ought to - you're obviously worth better than that by putting what you've put here.
It's always difficult where mates are concerned, I am sure anyone on here will tell you that.
I wish you well with it.