I’m (21F) in a happy relationship but still weirdly emotional seeing a former almost-relationship (20M) on campus. Am I being emotionally unfaithful?

Last year I became really close with a guy from one of my classes and eventually fell in love with him. We liked each other, but we couldn’t be together because of religious differences (he’s Jewish I’m not). It was a messy ending, we kept going back and forth thinking we could still be friends despite having feelings but that failed miserably and we eventually decided to stop talking fully and since then I’ve blocked him on all platforms only so I wouldn’t get the urge to contact him.

I’ve since moved on and I’m now with someone who is genuinely amazing. He’s incredibly kind, adores me, and I’m really grateful to be with him. I wouldn’t want to be with anyone else and I’m happy in my current relationship.

The problem is that I still see my old classmate around campus all the time, and he’s even in one of my classes this semester. And every time I’m around him it hurts so deeply. Not because I want to be with him now, I don’t, but because it hurts knowing that someone who once meant so much to me is basically a stranger now. We went from being really emotionally close to not even speaking, and it feels like there was never any real closure since we didn’t stop caring about each other, it just wasn’t possible for us to be together.

For some context, I grew up moving around a lot and I’ve always struggled with attachment and letting people fully go. So I think seeing him kind of brings up that same feeling of loss all over again.

What’s making this really hard is the guilt. I feel like it’s unfair to my current partner that I still feel this way sometimes. I’m not fantasizing about my classmate or wishing I was with him instead, but just being around him makes me feel sad and heavy, and I don’t know how to turn that off. It makes me feel like I’m being emotionally unfaithful somehow, even though I’m choosing my partner every day and don’t want anyone else.

Does this mean I haven’t fully moved on? How do you deal with the hurt and pain without feeling like you’re betraying your current partner?