Not over him

There was this guy I go to school with and two summers ago me and him were really close and pretty much always talking. I am truly convinced I was in love with him that summer and he said the same about me. Despite this we never dated but would always act like we were (strange I know). Anyway we kinda drifted apart and now we haven’t talked in almost a year. Anyway This guy I’m friends with asked me to be his girlfriend recently and I genuinely thought I liked him and I had felt that way for a while. So of course I said yes. But I find myself comparing him to the guy from 2 summers ago. I am constantly thinking ‘he does not make me laugh like he did’ or ‘I had more fun talking to him’ and I’m so frustrated that I can’t just move on and be happy with my current boyfriend. I’ve tried reconnecting with the boy from 2 summers ago and we stopped talking after a couple days. We are both completely different now and have changed so much since then. And I went months without him crossing my mind but the second I make a friend who happens to be male I compare them. Advice?