Is it wrong to want to tell my friend I used to have a crush on her even though I'm in a relationship now?

Two years ago I(17f) had this tiny crush on this girl (18f) and then it eventually went away because I wasn't friends with her and it was just a little crush where I found her very attractive. We became friends about a year after that and I no longer wanted anything with her, I mean yes I still find her very attractive but I wouldn't want to pursue it now.

I've been in a relationship with(17m) for about 4 months now and I'm still friends with her, but now that high school graduation is coming up I kind of want to tell her, "Oh yeah and by the way I used to have a crush on you but it's nothing now". I don't know how my boyfriend would feel if I told him so I think I may just keep it to myself, and I do not know how she would react to it . Just wondering what others think.

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