Lose-lose situation, need advice
About six weeks ago my second sister and I had a falling out. That falling out happened after she sent me an email explaining things she had been upset over the couple months she had been in the relationship and that she couldn't even see herself being friends with me for the time being. Her way of dealing with issues with me had always been to withdraw without warning and not contact me until she was ready to talk about what happened. Often it was days or weeks before this happened, and if I didn't pick up that she was upset and said or did something to push her to talk about issues or inadvertently upset her, it would only make her more upset. As such, this email left me with a lot of hurt, resentment and anger over how she decided to deal with her feelings and how she wouldn't provide the opportunity to work through them with her. Instead, she really left me hanging. Since then, it has grown into a very unpleasant situation.
Between her email and through talking to my first sister (who is in a relationship with her) I've pretty much ironed out by now why my second sister handled things the way she did and what she was upset about in more detail. Essentially, my first sister gave a blow by blow analysis of exactly why my relationship with my second sister went wrong. It was difficult to hear this, because she would tell me things from my second sister's point of view and I would immediately flame at how this wasn't right or that's not what I meant, etc. etc. It only hurt more because I still don't have the opportunity to talk to her, or at the very least, take "full responsibility" to her for my actions, which she feels I did not properly due in a couple of instances.
My second sister is still in relationships with our boyfriend and my first sister; ergo, she is still in very close proximity. I don't see her at all, but obviously she is a big part of the hearts of my sister and boyfriend, and there's still a (currently rather buried) place for her, too. The stress from being so close to someone yet unable to work out any issues at all, even to the point of being on speaking terms, is taking a very, very heavy toll on me. Try as a I might, through several sources, including a professional source, I cannot seem to effectively process the feelings I have about things with my second sister. It's really unhealthy for me. I've begun having anxiety attacks about it, bad ones.
Tonight, on a kink website we are all on, she removed everything about my from her profile, other than to say she was my sister, and wrote a lengthy, detailed journal entry about "her couple." I had already had an anxiety attack earlier today due to an unrelated cause, and this was the straw that broke the camel's back. I had an absolute, full-blow panic attack meltdown. I just couldn't handle the stress. For several hours I had to sit with someone because I didn't feel safe being alone. I have overcome the majority of my past emotional health issues, and for this to happen was very alarming and concerning for me. I am worried I am becoming a bit unraveled.
I think what grieves me most is the concern that, even thought things with my boyfriend, my first sister and I are perfect right now, and even though I plan on spending my life with them, my difficulties with my second sister will tear that apart, if not from pushing me away than by me getting to a place where I am all-around unstable and it destroys my other relationships, too. I worked, very, very hard for those to be built into happy, healthy relationships. I would be devastated if they fell apart because of this.
I am unsure of what to do. I want to talk to my partners about it, but my boyfriend usually ends up telling me second sister about when I am upset with her and then things get ten times worse because she will fight with him AND be more mad at me. My friends think I am not fully standing up for myself, but the last time I "stood up for myself" things just got worse. I need to defriend her on social networking sites because reading things she posts triggers these attacks, but I am not sure how to do that without making things seem even more awkward/fueling the fire. All I know is I want to stay in this relationship, I am very upset about the situation with my second sister, and I am slowly unraveling from the anxiety. Any advice?
“Be who you are and say what you feel because those who mind don't matter and those who matter don't mind.” - Dr. Seuss