It's been a year since I broke up with my girlfriend, we were a long distance couple for 1,5 years

I ended the relationship. I've seen problems from the start, but still tried to fix them for months which was irresponsible. I always tried to be patient and care for her, but eventually I was hurting myself and later realised this will go nowhere as she did not seem engaged in fixing the relationship. She had her own issues as well and I've barely convinced her to seek professional help

A few weeks before the breakup she noticed things are not going well between us, it was worse than usual, so she began what I suspect was to search for another partner without my knowledge
On one of our last arguments she admitted to having downloaded tinder without my awareness to "seek friends", which sounded ridiculous judging what kind of app this is. She also joined some fb LGBT+ groups for meeting people before, where I've noticed the posts were mostly about searching for a partner. I thought about breaking up with her for a while and her telling me that she downloaded tinder was the breaking point. I told her that it's over, because the trust between us is dead if she does things like these behind my back. She tried to convince me that she has changed in probably just a week after that, but I left anyways because this sounded like a total mockery. No one changes in a few days

I still dream about her and think about her. She is the only person I feel attracted to. I can not imagine closure with anyone else and no one seems romantically interesting for me. I can't help but still feel something for her. I imagine her in romantic activities with me despite what she has done to me and can not put anyone else in her place in those imaginations
But in my dreams there is a lot of aggression, I dream about physically hurting her and I think feeling betrayed is the reason. There was also physical violence in my house when I was a child so this may be where my behaviour in the dreams comes from

Is anyone here who was in a similar situation before? Do you have any tips about how I can process these emotions? Is time the only medicine for me to finally get over her? I just want to feel indifferent while thinking about her and finally move on. I feel like you rarely see people still not being over someone after a year when the relationship was just horrible