I then realized that I have been avoiding conflict with her throughout our whole relationship, mainly because of her hysterics and the way I feel after the conflict.
This is classic HPD/BPD trait and response, our W's seem to share this, so I understand how you feel and felt...man, do I know...
If it were me, I would say something along the lines of: "You are right W, I should have let you know about this beforehand. I wish I had done this differently, and going forward, I will, because I have thought about his and realized that these sort of surprises are not fair to anyone involved..." Others probably have better advice/words.
Then, FORGIVE YOURSELF...everyone backslides, or does something that shines light on something not yet completely discovered or resolved about themselves, etc. I still am dealing with the conflict avoidance thingy in myself.
If I could tell you how many times I have said to myself, in venomous sarcasm (which I can be very, very good at) "Oh, nice job, T2...you effin' a-hole, bet you didn't think you were/could/etc...."
As far as the friends or not question, if I were in your sitch, I think I would have problems with that until she came out of MLC and/or also resolved some of the HPD traits...but that's just me...YMMV...
We do keep finding/stumbling upon rocks to look under on this journey, eh?
T^2
In the depths of winter, I finally learned that within me there lay an invincible summer. - Albert Camus
Uncertainty is the very condition which impels people to unfold their powers.-Eric Fromm