Joshdp, I'm sorry to hear about what you are going through. One of the reasons I have been so glad to join this group is that other people around me, especially those who witness my best friend's behavior, have been less than supportive. Partly because they don't understand BPD or I do not feel it is their right to know about the possibility of my BFF having it. So the responses I have gotten when trying to gain support or talk to others about it has mostly been things along the lines of "She sounds like a b*" or "Why are you friends with her?" and more of the same. It is hard when I try to reach out for support and end up having to justify my friendship, especially when I am already at a place where I feel vulnerable.
This is a safe place. You can speak freely, and get support. We all understand even if your situation is different, in some small way we all still understand.
I would recommend a couple of books to you. Both are very helpful for getting back your piece of mind and simply feeling more able to handle the behavior of someone with BPD.
www.amzn.com/1572246901Stop Walking on Eggshells: Taking Your Life Back When Someone You Care About Has Borderline Personality Disorder Paperbackby Paul Mason MS and Randi Kreger
www.amzn.com/1593856075Loving Someone with Borderline Personality Disorder: How to Keep Out-of-Control Emotions from Destroying Your Relationshipby Shari Y. Manning PhD
The one thing that helped most was knowing that it wasn't me in the sense that I hadn't DONE something wrong. It was simply the way her disorder read the information I was giving her. What I did or didn't do, what I said or didn't say, what my face said... .or what she thought it said, which is a big one.
Also, as far as emotions you need to try to get a handle on yours. Before you have any interactions with her in a day take an inventory of where you're at alone (even if just in your head before getting out of bed). Are you happy/sad/content/mad? I had to learn that if she was in a bad mood that day it didn't mean I had to be too. This was most important because I began taking home her bad days with me, then my family would have a bad day. That wasn't fair to me or them. At first, it felt somewhat cruel that I didn't SHARE her state of being, but I had to realize it is HERS, not MINE. When she has a reaction to something or she WANTS a reaction from me, I have to carefully think about what I actually feel and not let her influence my feelings. This is difficult and even now I struggle with it some. We are both very emotional and empathic so it takes a lot of work to manage this one.
Take care of yourself and I hope you can get the support that you need.