I am devastated from all of this and can't figure what I did other then support and love her. I some odd way I miss her and deeply worry about her, but I know I can't be the one that saves her unless I put myself back into this environment... .but she's locked me out of it right now. What can I do?
Living with a BPD is a endless rollercoaster. No matter what you do, there will be conflict, drama, accusations... .That will never end. It's not about you - it's about her. YOU CANNOT SAVE HER - drop that thinking immediately.
I know that ending a 6yr relationship is painful - do you really want back in? If so, there is much on this site you can learn. But remember that no matter what you do, SHE will always have the inner conflict. I would suggest spending a few weeks with no contact. Really try to decide whether she is worth the endless conflict, or whether a more stable partner would be better. Sorry to be harsh - but at 50 you have a lot more of your life left, and this is at least your second relationship so you don't have that "she's the only one" thinking... .