Lasting (Psychological) Impressions

Ok, so this story will probably sound a little strange, but I just have to get it "out there."
I have a slight obsession with this guy I used to go to high school with--we'll call him SD. SD was one grade up from me, and I met him my sophomore year at band camp. At the time, our band camp was actually a camp. As in, we went to the state park, stayed in cabins with bunk beds, and practiced in a football-sized field in the middle of the woods. Anyways, after a full day of practicing, we always had a few hours before curfew to hang out around the cabins. SD was a very friendly guy and didn't have a problem hanging out with the "rookies" (sophomores). That, along with the fact that a lot of my positions on the field were near his, allowed for us to spend a good bit of time getting to know each other. Oh, did I mention that he was HOT?? Yeah, anyways. Band camp was only, umm, 4 days, but we really did get to be fast friends. Over the course of the 2 years we were in school together we really got to be good friends, but the whole time, I was completely and utterly IN LOVE with him. Back then I wasn't shy, but I wasn't very aggressive, either. So, he KNEW how I felt, but I wasn't going to START anything. Over the course of those 2 years, we had a lot of "moments" but never dated. Still to this day, I don't know why we never "hooked up" (as in dating, not other stuff). Oh, I could go on & on about all the incidences and events that could have led to it, but it never happened. I know I wasn't repulsive--at least my various boyfriends didn't think so. Sometimes I think that if I had just been a little more BOLD, maybe....but, alas, it wasn't meant to be.
Now fast-forward: Since his graduation in 1998, I have seen him "around town" on maybe 3 or 4 occasions--SINCE 1998! That's not much, right?! Ok, so why can I still remember all the tiny details of every important interaction that we had? Why can I still remember the things he said to me about not wanting to "hurt a friend's feelings" (the only conversation we ever had about our non-relationship), or how he looked at 7:00 at night after a full day of sweating at band camp, or how funny "Monty Python" was when I watched it with him, or how moved I was to find him alone, in the dark, in my best friend's room, playing "Stairway to Heaven" (one of my favorites) on the guitar.
Why do I still have DREAMS about him?? Yes, I, a grown, happily married woman, still have dreams about my high school crush! These dreams come at random, they involve random situations, and they never have a beginning or end. It's not like there is a story about me and him, it's more like my life is going on....then there HE is...."hello, how are you? It's been a long time..." And usually he gives me a very nice, friendly hug--then a semi-intimate kiss. Before I was married, I never thought about the kiss. I would laugh & compliment him, or something. But, in the last dream I had (2 nights ago), when he kissed me I pulled away and said "Wow! That's funny!" SD says "What's funny?" Me: "Just thinking about how much I LOVED you back in high school, and this is the first time I get to kiss you!" He starts in for another, with a smile. And I say "There's someone I want to introduce you to. Do you remember Richard? My husband." (SD & Richard knew each other in band, too.) And that's it. End of dream.
I mean, what kind of psychological impact did this man leave on me that even now, 7 years later, I still can describe to you how sexy his eyes were when he woke up, cuddled in my lap, after 3 hours of rough sleep on the bus!