Hey, I hope everyone is doing okay. I am a new member (sadly) but I am glad to meet y'all!
My ex-girlfriend (diagnosed pwBPD) and I were together for about 4 & 1/2 months. We made acquaintance 2 or 3 months prior to that, were seeing each other pretty much everyday because we had a lot of friends in common, and quickly become close friends. We would often smoke, drink alcohol, eat out, study , or even just chill and watch a movie together (not always one-to-one, but rather with those friends in common). She and I had a lot in common, either personality traits or centers of interest (same favorite artists, same favorite movies, same opinions, etc. I'd almost say pretty much the same mentality). This obviously got us even closer untill we started dating.
When we got together, we were living in the same appartment. I was happy to have her in my life. Everything was going very well between the two of us; she would often compliment me saying that I am hot, handsome, kind, and funny, and so would I. We would cuddle so much, have sex, watch movies together, go out together, eat out together, drink together, etc. Even though there were some small problems that would arise between the two of us, it'd only take us at most a couple of hours to solve them and move on (trust me I am not delusional or trying to blame her but 99% of the time she was the REASON of these problems, even though she did not necessarily mean to). Then comes the day where we had OUR BIG FIGHT, and I messed up. She then went Silent Treatment for a couple of days untill I reached out to her, we talked about it and "moved on". I reckon that what I did/said is not something you can quickly move on from, I am fully aware of it, but trust me we did with time, and I am not gonna lie I was/am grateful that she gave me and us another chance back at that time. Anyways, time passed by and everything came back to normal, in fact I felt and we both agreed that that problem somehow brought us even closer together, and she let me know more than once that she actually forgave me and is glad we were able to move on. We came back to be a happy couple once again even though we would once in a while have a small issue or two, we always managed to get through. Anyways, we were in love and made sure to tell one another that more than once a day. She claimed that she loved me so much, would not imagine her life without me, said that I was the perfect man, wanted us to marry and have kids and pets, etc. We even had some short-term plans about the upcoming academic year (because marriage and kids are considered long-term plans given that we're still

uni). Long story short, there was no single problem/issue between the two of us; to the contrary.
On another note, I personally had some family issues and was not doing that good mentally, and I let her know multiple times that I hold on to her and that just talking to her and having her by my side does me alot of good, and she'd often tell me she loves me, would stay by my side and obvisouly wait for me to "heal" and be a better version of myself.
Now (we no longer lived together in this phase), there comes a week where I could not reach out to her properly, she would go a whole day or two without giving me her news, and I let her know that this is not something good for a healthy relationship because I can get worried about her (given that she is mentally & physically ill) and she'd apologize and tell me that she knows I am right and she'd not do it again. Yet she'd just repeat the same behavior two or three times in the same week and go MIA for another day and would text me later as if nothing happened even though I let her know that I was not okay. Ultimately, she went MIA once again and had to let her know once and for all that I cannot accept such behaviour, and that: 1/ I actually miss her and need her in my life (fear of engulfment?) & 2/ shall she ever do it again I might leave her because it was clearly tearing me up (fear of abandonment?). Her answer was "I really don't know what to say". We then went 1 or 2 days with no contact untill I sent her a text in order to talk about this situation one last time so that we could move on. Then, her answer was "I am sorry I don't myself with you anymore, I lost feelings for you because I could not forgive you for what you did to me" (refers to the fight I talked about above). Is this common for a pwBPD? I mean she done let me know more than once that she forgave me for it, and that she was to move on because she loved me. Trust me we talked about this more than once, and she always told me she forgot about it and was able to move on. And bear in mind that THREE MONTHS passed between that fight & her dumping me. How could she break up with me for something that occured months earlier, saying that she could not forget about it, while she and we clearly did and both agreed on that?
At first I was flabbergasted how she could go from "I love you so much you're the man of my dream" to "I don't love you anymore" in literally 24 hours! I was so sad and mad, and THANK GOD I found some "answers" in these forum as well as in other platforms such as Quora where people experience pretty much the same as I did. I can't imagine how would I be doing if was discarded like that, without finding these answers.
Eventually, I reached out to her one last time to let her know that there are no hard feelings and that I truly wish her nothing but the best in her life, still didn't get an answer and don't expect or want one, tbh.
Now, I had pretty much gained some knowledge about the situation: I know that I was idealized

the beginning, then devalued. I am now painted black, etc. But if you could give me further insight about my situation, I'd be very grateful.
Thank you lot!