I'm sorry you are going through this, I understand this too, even though I am not diagnosed with BPD. (I have a lot of the symptoms though.)
I do the same thing, too. I push and distance myself from people and it's worse than before. I am even distancing from people I love since it feels so uncomfortable to be around them. It makes my skin crawl. I don't know why I do that to them. I know why I do it to others, though. There have been one too many times where something happens in which causes me to become extremely distrustful and wary of others and their intent. I also believe I'm always to blame, somehow, someway. If I didn't directly do something I'll feel I didn't do enough or just bother people by merely existing. It's a big pain in the ass because I want friendships but this causes me a lot of fear, anxiety, and I'll start sh again.
However. there was once where I could tolerate being alone, almost completely alone, and isolate inside. I never talked to anyone, and I only heavily focused on playing games, reading, or whatever. I did this for awhile. I won't lie, it was still hard to do. Sometimes I would just start crying uncontrollably when no one was around for about half an hour, but I would be able to pick myself up again. I left everyone alone even though people always found a way to fuck with me, though. It was the most stable I've been in years. I wasn't happy, but in my painful, sore solitude I was at least the bare minimum of content I could be. It helps that I had a cat with me though, without her I think it may have been harder. But it is possible.
My mistake was starting to bother trying to have friendships. This has always been a problem with me. Due to how I grew up, I'm extremely vulnerable and just blind. People would compliment me, made me feel human, and all of a sudden my brain pumped a lot of serotonin I didn't know what to do with. I felt alive again, I felt like I could go on. Of course though, my luck isn't ever good, and that all pretty much stopped when the inevitable bullshit started. More drama, more incidents, more lies. I had to pick sides and see things split apart, just as it always does. I was put into positions I had no control over that made me look like an asshole no matter what I did. Doesn't matter if my intent is always for good, doesn't matter who I'm 'friends' with, doesn't matter what I say.
Fast forward to right now and I feel so stupid and pathetic. I let myself be used. I let myself be hurt. I dared to even try and forge connections, even just to have fun with others. This is my punishment, a punishment passed down from generations of broken people onto me.
TLDR; Although I just wanted to let you know I totally empathize with you, if you want to not be lonely you have to be willing to take risks. But because you have BPD, you already have a brain working against you. I don't think it's impossible, but you probably have to be uncomfortable, be willing to take risks, and somehow not be hurt when things do happen. You have to unfortunately just take people's word for it and try not to assume. Friendships and relationships are all about trust, and you have to be willing to suffer through that hot mess to be able to get to the other side. I think the rewards from it could be good, like you meet your bestest friend ever or something and you guys always hang out, but please do consider how it might make you feel.
I think it might not hurt to get some insight from others as well. I don't know. Hope this post helps you OP.
