I'm currently a 23 year old university student (who doesn't really attend much) diagnosed with BPD since i was about 17. I've gone through the classic relationship turmoil before and my patterns are very toxic with a lack of trust, fear of being cheated on due to past events and intrusive thoughts ruining good moments. I met a women online who i got to know and fell in love with, and she fell in love with me too. She is a PTSD/CPTSD sufferer herself so some of our issues are slightly similar, when our relationship is going well it's phenomenal she's the most loving and supportive person I've ever met, she''s funny, interesting and cute and i do my best for her because i care so much about her. 

Here's the problem. I cause the problems, a lot of the time. If she causes them, i can't even tell if it was her fault or my fault. I blame myself so much and so heavily whenever anything goes wrong in our relationship and I'm so terrified to lose her. Her behavioral responses to rough patches have also been very painful for me, spending time with her ex, blunt or aggressive conversations ect. She has her own problems and we're both trying to improve slowly. We met for the first time in person two weeks ago, it was honestly the best two weeks of my life even through episodes on either side we were there for each other and managed to work things out. But she left a few days ago and now I just feel so lonely, She lives with her ex and although there's no feelings between them and she wants him to leave the overthinking and exposure to him eats me alive. I feel like I'm drowning slowly and I don't know what to do to pull myself up again, The worse i get the more strain it'll put of our relationship which turns into another cycle of guilt and shame and fear.