I love my boyfriend but I feel like I'm not over a crush from a year ago

A year ago I was really in love with this guy, I went a little crazy and a little fast on him (told him emotional baggage too soon, wanted a relationship despite us both barely talking in real life) and he left me with a lot of "what ifs"

Just now a friend of mine told me she chatted with him last weekend at a bar. I got this whole rush over me thinking "what'd he say" and sort of fantasizing about seeing him and showing I changed a lot in a year. Not even something to do with love, just talking and proving a point?

I feel really shitty about it, since I feel like I am betraying my feelings about my boyfriend. I love him a lot and he's my firts real relationship, everything fell into place with him and at the right time. He knows about me and old crush. He's the person I tell everything and I want to tell him this but I'm not sure how and why.

I'm not sure how to deal with this, and I feel so guilty already about even thinking about the old guy. I saw him around a few times and the rush isn't permanent or anything when I see him. But still feels shitty. A few weeks ago I talked to his friend (he was behind him) and he just dreamily stared at me, not conversing with us, which made me kinda uneasy but I'm not sure in what way.

What should I do? The bar he goes to has good music and I feel like I'm more afraid of something happening than just him... or that I have something to prove. Should I tell my boyfriend ?(we're really open about feelings, but I'm not sure how I would feel if he told me something alike)

(Not sure how to flair on mobile)