To be straight from the beginning I am not diagnosed with BPD, I am not looking for diagnosis but I believe there is significant common ground, I would appreciate some understanding. (is it just me or do I sound like an asshole when I write that?) 

What I know I am however is overwhelming empathetic, I walk in a room and I sense everything haha, nearly every cue, every expression, seared into my little forts I build in my head. 
I had Myalgic encephalomyelitis when I was a child (CFS, ME etc ya know) from 7 to somewhere around 14 it is a blur, while this was happening, I went through extended physical and emotional abuse, nothing too sexual apart from a few attempted impalings with various objects or being forced to watch girls get changed, at school, my age, otherwise I get my skull bashed around, to be frank I know relatively speaking my childhood was a walk in the park.

All this has mixed together to make me very unstable, it has gotten much worse since I was 16. Yet I can't express it or discuss it without dismissal or ridicule.

Yet my Personal Trauma, it doesn't bother me. My Best Friend, who showed me kindness, she was raped when she was 16, beforehand she was the type of person who would believe anything was her fault, she couldn't keep stable relationships, we supported each other very well aha. 
Afterwords, everyone, her family, friends they all told her it was her fault. Afterwords she wasn't much different, it was subtle but radical, suicidal etc. 
I couldn't save her, help her, like before, if anything at first I had a coincidental breakdown I didn't know she was raped, told her I loved her, told her about my very intense guilt ridden sadistic sexual fantasies, and ofc got pushed away, and so I went a little crazy, All to myself, I internalize my aggression. I feel so much guilt, I kept thinking of a time a year beforehand I wrapped my hands around her neck just because another one of her fun boyfriends hurt me when I was younger, I found that very arousing her fearful confused eyes, then I remembered empathy dropped her apologised ran off, she found me and just sat with me, she knew.

Then I remember the nights regaining her trust, all night a couple of times talking her away from suicide, I could never tell if I'd see her the next morning, she started having seizures spent time in a ward, that must have been so scary, all the screaming, crying children, can you imagine how that felt, what is wrong with me? Am I going to die?

In the end she came back to me after one of our intense arguing sessions weekly, and told me I had changed her, for the good I had taught her to be self-reliant, to believe in herself and more importantly to stand up for things she knows she needs or wants. I was the only one who told her that it wasn't her fault, none of it was, I had to keep repeating it over and over. 

Then we fell out a several months later, my fault. That was the darkest place I have ever been, I remember tanking my grades, a lot of crying, slicing my hands open and finger painting. now nothing gets me emotionally aroused other than anger.

See I thought I was telling her I loved her, we were recently talking again, clearer and with catharsis, and apparently what I was really saying sounded like I hate you, I want to hurt you, strange I honestly thought I was being clear. I wasn't and as we talked we bonded, this time differently more sex talk, flirting etc, I was very happy to learn she was quite keen on the idea of me tying her up haha, but then that was all we could talk about, her ex boyfriend came back in the picture, I became more dependent and god we stress each other the fuck out, I hate being close to people, and unfortunately so does she, and then I think I really messed up, she begged me to get help. Now she is gone for good.

Now I am the Crazy one, but then it was always that way. I'm so sorry for the rambling, I need a group of people and some people within that group who are similar in some ways to me to just say it to.
I feel like a monster, like I am wearing a person suit, a mask, I can't tell if I hate the Woman I love, I love her, I hate myself, or Like myself too much, I can put myself perfectly in her shoes, put myself in anyone's shoes, I know how it felt, I only just realized how it effects me, I can't tell anyone, especially not her. I feel so stupid and foolish, I thought I was crying, I should be, I want to, I except I feel kinda nothing, yet everything too, that everything is a lie though, I can switch it on and off. 

It means I might be wearing this mask of self-described guilt, that I feel like I monster, I am scared that without it, I am exactly what I fear to be the most. Although because of her, I know I will keep doing the right thing, I am studying psychology, I can help others, pretty well I do a lot of volunteer work, she always claimed I could mind read her, just I can't help myself, and no one knows what goes on behind my mask, except her and she begged me to get help. That scares me.