When I was in high school I meet a guy that was a student in the same school as me, we became really attached to each other in the first days and everything after that is a hurricane. He never was serious about anything, I was an idiot and stupid. By the time I was dating another person, but when I recognize I was catching feelings I broke up and tried to do the right thing, even after a bad start.
The point here is, he have bpd, everything that was morally wrong he blamed the bpd. He lied about everything to make me believe that we was meant to be, I tried my best to engage in his interests too but I was failing aways. Some months went by in this carrousel of feelings, some abuse here and there, I would do anything just to hear that he loves me.
He started to slowly go away without telling why and my depression started to eat my last hopes.
In the beginning of 2019 I started to notice strange things, I was obsessed with him, I wasn't eating or bathing by myself anymore. He was cheating on me with a freshman, not only it made me go insane but I started to think about hurting her.
That wasn't only that, he send nudes to another girl on IG and the girl told me and sent me proof, I cried my lungs out but I didn't want to give up on him.
One week later, the day of my birthday, (yes the 3rd girl already) she bite his neck and I saw the mark. That was horrible to see, but at the end of the day he picked flowers for me and brought it with his mother, I didn't had courage to end right there. In the end of the night, by messages, he ended the relationship saying that he didn't saw me as a lover anymore.
I just asked for one thing, one month until he goes back to bitch number 1°. Three days later he was with her, in the same school I was, kissing her and other things.
Okay now you may think, this was the end of the history but fucking no. I had some quickly dates but none of them ended well, if you understand what I mean, at this point I didn't believe anyone could love me or be nice to me. I just wanted to feel loved, even if it means being used by the night and beaten up by the day. I dressed up like a whore and walked up and down that way no matter how I felt inside. I wanted to make him feel bad for what he did to me, I couldn't forgive nor forget.
End of the year, I was just counting the days until I was going to try to kill myself, he showed up and cried in front of me, he was sorry and wanted to try again. I said okay, let's try for a week. He abused me one more time and went beck to that girl again.
I was violent and hopeless, I tried to kill myself and I warned him about it all, I just wanted to see him saying that love me.
I was hospitalized and discovered that I have bpd, at first I didn't understand and didn't believe cuz everything I learned about it was from him and his horrible way of using that as an excuse.
Some months went by again. I was still talking to him, or trying at least. On an event we hang out together, just us, was kinda cute for the first time cuz I didn't felt violated or abused or crazy.
On an video call that I was painting my hair and wanted company he started to show his... You know what, I tried to be avoidant I swear, he was trying to make me fall again.
One day I was searching up his social media, here on reddit, and I discovered that he was dating, HE WAS PLAYING GAMES WITH ME AND ANOTHER PERSON. I was so frickin mad about it, I didn't talk much after that cuz I blocked him on everything.
It was 2 or 3 years ago. I still have nightmares EVERYDAY about him.
I'm in a relationship right now, for the first time in my life I feel that my feelings are valid and that someone cares for me. I told him about this story, he is pretty aware of the mess that I am too, but I don't have the courage to say "I dreamed about my ex abusing me again, that's why I hate to sleep".
I don't know anymore what to do or who to talk, I can't pay therapy, please if anyone have any tip on how to end those nightmares...

Sorry for the long post and sorry if I wrote anything wrong, I hope you guys have a wonderful day... Bye