retroactive jealousy about a 2018 hookup of dh's that I previously did not care about... why now

married 14 years, monogamous till 2 years ago, in the LS now and mostly good. dh in 2018 (before kids, before LS) had a brief thing with a coworker that we addressed at the time, I forgave it, we did counseling, we moved on. it has not been a thing in our marriage in years. a couple of weeks ago we were screening a new couple on the app and the woman on their profile looked vaguely like that coworker. not even closely, just the same general energy. and ever since I have been spiraling about the 2018 thing in a way I havent spiraled in 5 years. I went back into old emails. I reread the texts I had screenshotted at the time (yes I still have them in a folder dont @ me). I asked dh weirdly specific questions about what she was like in bed, which is something I never asked at the time and DEFINITELY did not want to know now in any sane state. why is the LS reactivating something that was buried?? is this normal?? was the 2018 thing not as resolved as I thought, or is the LS just stirring up jealousy capacity in general and it found something old to land on bc the present is mostly fine. I am scared to talk to dh about it bc I dont want to make him feel like Im rehashing something he apologized for and worked through. but Im also unraveling alone over here.