My girlfriend (22/f) and I (24/m) have been together for about 11 months. There's been so many great moments, and unfortunately a lot of lows. 

First of all, I really do love her. We started dating rather quickly after meeting through mutual friends. Things were great at first, but a couple of months into our relationships things started to happen. She always compared me to her ex, put me down, stated fights over small things etc. Then things got physical. She became very physically abusive towards me. She's a petite girl and Im an average sized guy. I didn't really think much of it of first until i started getting bruises and cuts after fights. anyway about 5 months in i was starting to feel like our relationship might not work, so I suggested we take a break. At the time she was using my car almost everyday to get to work. After bringing this up one night, she lost all control. She screamed at the top of her lungs and was physically abusive. A neighbor called the cops and I got thrown in jail and was charged with felony domestic abuse, even though i did not lay a finger on her. Thankfully, after the case was reviewed, the charges were dropped. But i did have to pay a very expensive bail to avoid spending 5 nights in county jail until my court day. 

After the ordeal, she apologized and admitted she had BPD. I vaguely knew about it, and did my research about it. Her behavior made sense to me now. I took her back and tried to work it out with her. 

I do not have BPD, and can't imagine what it's like. This is my side of the story and I'm trying to be as honest as i can. My behavior before the jail incident wasn't perfect. During fights i would always try to leave, i'd break with her, and say mean things. Afterwards i tried to be mindful about her BPD but i resented her a little. 

We had a our good days and our bad days. but i was always there for her. I drove her every where she needed to be, bought her flowers, paid for shopping, food etc. 

She cheated on me with a random guy she met at work. He was a customer at her job and asked her out and she said yes. She lied about getting drinks with her old housemate and went out with him. She gave him a blowjob that night and later came to my house to watch a movie with me. 4 days later she went out with him again and had sex with him in the afternoon. i picked her up later that day and bought her dinner. 

She admitted to me what she did a few days after. I couldn't believe it. She apologized profusely and I took her back. I demanded that she never talk to him again, and she said they were friends and she wanted to maintain a platonic relationship with him. I lost my shit. after a couple of hours, i found myself consoling her, trying to convince her she that she isn't a terrible person.  anyways she finally deleted his number and whatnot about 2 days later but said she felt heartbroken about it. It kills me just typing this out. at one point she said that they were very sexual compatible and even said the sex was very good, without me prompting a question about it.

I realize that our relationship was not good before she cheated. she said she didn't feel special and his attention satisfied that need for her. 

I still love her and we're still together. We've made good strides and are in a good place right now. 

But still think about her cheating on me everyday. I know she has BPD, but she was very nonchalant with her apologies. I almost feel she saw her actions justified.  and recently she has been very paranoid about ME cheating on her.

idk I'm just venting, i haven't told anybody about this. Any input is greatly appreciated. 
