<human>: Give me a shortened version of the text

I have been dating this girl for three months now and everything is amazing, seriously we get along great, I find her very attractive, no complaints. We both go to the same school, along with an ex of mine who did some really shitty things to me and I in no way want to be back with.

And yet, I can't stop having these occasional intrusive thoughts or impulses any time I see her on campus or at random moments sometimes during the week, and it pisses me off because I am genuinely happy with the person I am with and I don't want to go back and I don't know why I can't just forget about my ex. I get kind of angry with myself, actually. I don't talk to my ex anymore, full no contact and all that, but it just feels so wrong, like I'm subconsciously cheating or something and I just want some advice on how to make this go away.
<bot>: Happy with current girlfriend, having occasional thoughts about ex who I run into from time to time, just want to forget her and be with current girlfriend.