One is an ex who has since passed away. I was totally and completely besotted with him. He was a few years older than me, though, and at that time and in that place not really interested in me for the long term. He moved away and even though we later ended up in the same city, we never really connected again.
Another is a guy who I met just as I was about to make a big life-change - smart, adorable, but just coming out. I was more looking forward to what was coming up for me than the here and now, and at the time not interested in the whole coming out drama. I think he really had a serious thing for me but I just deflected it. We've become facebook friends within the past year - he still looks great, 25 years later.