The story is like this:
Context
We have been together for little more than a year. I had to move due to job reasons about 2000 km out from our home city, just after we started going out. She suggested moving in with me, and it felt good so we planned for that. She moved in last September.
In the meantime, I had some rowdy messages with a friend that I knew would not get over well with her, but I really didn't mean nothing of it. It was basically horse-play and it was never ever ever meant to be anything but. I haven't cheated on her with anyone, not emotionally nor physically. My gf got to those messages and freaked out. I apologized and realized that was bad behavior and cut it off.
Her cheating
Shortly after that, and after moving in, it's when she cheated on me. She went out on town with some visitors, omitted that she lived with me and basically fooled around with a guy. I got wind of it by accident and almost threw her off the house. I calmed down however and decided to give her another chance, mainly because I saw myself reflected in my own bad behavior and that I was able to change it and being more honest so I hoped she would too. It hurt me like a bitch, and was hurt for a while, yet I think I took as an opportunity to grow. Please note she never stopped being loving and caring all while she cheated on me.
She started going to therapy, because up to that point she was having very destructive behavior, like suicidal thoughts, strange paranoia when drinking, low drive to do anything, a horrible job as well as medical problems (Throat infection followed by yeast infections, blefaritis). The sex life up to this point had always been so great and even though we had challenging times with therapy/health/job loss, sex was always so intimate and satisfying that I felt everything would be alright.
Recovery? Anxiety sets in
We dedicated ourselves to improving all those situations and improve they did. She started her own business and it's starting to take off, her medical issues are diminishing and she's been 2 months out without a psych episode. It's almost like it's inversely related with sex life, as the best she gets, the worst the sex life is. She has stopped getting wet and claims to be nervous and anxious about that. Since New Year's eve we have tried about 3 or 4 times only, and one time we couldn't do it because of how tight it was. I have suggested doing other stuff like oral and fingering and she goes along for the first two times and then completely forgets about it. She never initiates any more, and when I do, I get tenderly rejected.
Since her business is taking off, she seems to be always on the phone and I have seen some strange notifications when using her phone for w/e. She talks to me about 1/3 of her conversations online, which is not a big deal for me usually, but when coupled with notifications from dudes or something as well as her past behavior, I get very anxious.
Now
While my job has its things it's not stressful, and my life in the new city is boring, but easy enough. I am making good money after years of studying so I feel good in that regard. But somehow, my love-life is feeling very dreadful. She went home for some weeks due to family issues and I felt so much at peace, like I haven't felt in so long. Just in the last two weeks my feelings have changed from "Is she doing this? Am I sad? What can I do?" to "I just deserve to be happy. I DO remember not being jealous in my previous relationships. I am OK personally."
During that time, a friend of mine asked to start chatting to a gal friend of her that was going through a really rough patch. I did, and it felt good. This gal friend then started to heavily flirt on me and I felt very responsive. Aware of my past behavior, I cut off this talk due to respect to my girlfriend, but now I am left wondering if I am correct in staying in this relationship. These anxious feelings have been here for the last 2 to 3 months, and in no way started with me chatting this gal, but it only brought them even more to the forefront.
We have made sacrifices to move to this city, it's not as easy as "ok you go away now". I would not want to break a meaningful relationship on a hunch or a fleeting feeling, yet it feels like it's not going away soon. I don't feel like I can get to trust her completely as she should deserve from a relationship.