How can I [20M] avoid feeling guilty about finding someone else attractive, even though I don't have any deeper feelings for them while I'm in a relationship?

Here's a revised version of your text: "I experienced sexual coercion from someone else when I was 15 and in a relationship, and since then, I've become hyper-vigilant about any feelings of infidelity or the fear that I might cheat again. Whenever I'm in a class or similar environment and I notice an attractive person, I immediately feel a wave of guilt and perceive it as an impure act. Is there a way to manage these feelings and make them less burdensome? My partner (20NB) has reassured me that these feelings are normal, but I still find myself feeling guilty."