BPD: Feelings of Depersonalization and Feeling Used

I have BPD and am currently going through a breakup with someone who also had BPD that I formed an unhealthy FP attachment to. We ended things last month, and hadn’t seen or spoke to eachother. Then, last weekend we went out for drinks and I stayed at his place and we slept together and kind of just pretended the initial split never happened. Then on Monday, he told me we couldn’t see eachother again, he doesn’t think we’re compatible and that he just needs to be alone for while because he doesn’t know what he even needs or wants in a relationship. As much as I understand, this obviously broke me to pieces and I am struggling immensely. 

After we hung out over the weekend I kept thinking of our interactions the next day and currently and it all feels like a dream. Like it didn’t happen. I know we had a talk where I told him that I had missed him and told him about my first love, but I can’t remember what I said or what he said and it doesn’t even feel real. It’s like I was wanting this so bad and actually got it that it couldn’t be possible. When i think back on it I see myself in a perspective other than myself, and that my words were not actually coming out of my mouth. I’ve had an experience like this before with a FP where we had not seen eachother romantically for a while, but we stayed friends and worked together. we were both in a relationship but I had been secretly wanting to still be together. It’s like I needed to know he still wanted me and was interested in me, nothing else mattered until I was able to get that. I was no longer interested in my partner, and thought if I was able to get that from him everything would be fixed. We ended up having sex multiple times in one night and again, it did not feel real, too good to be true. I see myself in third person whenever I think back on it, like the decisions I was making were out of my control and it scares me