A brief background:
We're both 18, have been dating for a year and a half, I'm in University, and she works full-time. We met at Church and fell in love after a couple of months. This is both our first relationship and we both lost our virginity to one another. There is history of abuse in her family from her mother and her father who are separated. Her family is poor and they have always been poor, she has many siblings and half-siblings, all being raised by her single mother. My ex gf's father was diagnosed with bipolar (Don't know what type), and my ex gf's brother is also diagnosed with bipolar (It is very obvious). My ex gf is diagnosed with depression and anxiety, but has been unmedicated for years. I suspected she was bipolar or had some other behavioural illness but never really paid attention to the red flags.
However she displayed:- Fear of abandonment (She often needed me to reassure her that she was pretty and not fat, and she said many times that I was too 'good looking' for her, when in fact she is VERY beautiful and weighs like 110 pounds)

- She definitely displayed characteristics of splitting (She either really LOVED something/someone, or absolutely HATED it)

- Self-harm (when we got into arguments and she was frustrated, in pain, or stressed , she would resort to cutting or hiting herself on her head, and in some cases has attempted to overdose on multiple occasions)

- Impulsive behaviour (she often spent a lot of money out of impulse buying)

- Uncontrollable emotions to those closest to her (To others she appeared to be completely 'fine', it was absolutely scary because I knew what she was really like)

- Absolutely TERRIBLE at coping with stress (As soon as anything became too stressful she either gave up or walked away)

- Never takes accountability for her actions (Even when she was wrong, she always thought she was right. It was ****ing scary.

The relationship moved extremely fast (mainly because of her), within months we had become so sexually experienced because of her high sexual demands. That's one thing I really miss, the sex was amazing. She often spoke about marriage, having children, and went on and on about how 'perfect' I was for her, how 'lucky' she was. 6 months into our relationship, due to her stressful family situation at home, she moved in to my house. My family lives in a big home and its often empty. For the most part my family was accepting of her (Except my mom, my mom always thought she had some personality or behavioural issues

). We pretty much lived together for the next year or so until she broke up with me just a week ago. During the last couple of months of our relationship she often said how I neglected her, I mistreated her, I was emotionally abusive, and I took her for granted. The scary thing is all I could remember is showering her with love, attention, time, and I absolutely respected her. This was only particularly true when I was so busy with my final exams and assignments and I didn't have enough time for her, around this time she also told me about a co-worker who was flirting with her (but she said she had no interest in him), I trusted her so I did not think anything of it. Keep in mind this was about a month ago, and ever since I finished my school work I was sure to give her the crazy amount of attention she needed. Apparently she seemed satisfied... .
Fast forward to last week we got into an argument. She wouldn't stop snapchatting one of her male friends, which I have no problem with, but she was deliberately trying to get me jealous. Sadly it worked and I told her to F off for the rest of the night and let me sleep. The next morning she moved out of my house. No warning. No explanation. She just left. She called me later that day and told me that we are broken up, and maybe if I change (what a joke), she would take me back.
She became EXTREMELY cold, distant, very confusing to understand, and in some cases I think she also became manic. She started befriending co-workers, hanging out with friends she usually doesn't, and doing activities she never does. She was unnaturally happy, and the worst part was she began talking to one of the co-workers that have been pursuing her.
After a long conversation of me picking at her, she finally admitted that she made out of with this co-worker and she 'thinks' she likes him. She says he treats her so much better than I do, and that I don't deserve her. And blames that all this happened because of me. I was completely blind-sighted and felt extreme betrayal. I decided to go into NC so I could heal and try and understand this situation, but it's complete ****ery and I gave up because I think she is sick and there is no way of me understanding what is going through her head.
Overall I am really hurt. I can't say I don't love her, we have so many great memories together. It feels like she is an entirely different person just from a flick of a switch. I know she is no good for me, but at the same time I want her.
I know I'm young and I should move on, but I still would like some insight and stories from you guys about similar situations.
Thanks.