I think every has songs that have this effect on them. Music is a great key to memories.
I was reminded last night at work how much a song can remind me of the past. I always sing to myself while I'm working and last night I started singing "That Summer" by Garth Brooks. That song has a very deep and personal meaning for me because it reminds of the first girl I ever slept with.
I got to thinking about it, and I tend to associate a certain song with the girls in my past. For example, the song that reminds of my first love is "Life's A Dance" by John Michael Montgomery. The first line of the song... "When I was fourteen I was falling fast for a blue eyes girl in my home room class.." Except for the home room part, that was totally true for me. I was fourteen, she had blue eyes, and I definately fell fast.
As for "That Summer", a lot of my friends know that story. When I was 16, I spent a summer in Michigan helping a friend I met on the internet fix her house up. We had never planned for anything to happen, but it did the first time I went up there. I learned a lot from her and although it ended awkwardly, I still think about her sometimes, and when I do I smile.
When I was 18, I fell harder than I ever had. Those who know that story know it ended very badly. Before it was all over, I had a nervous breakdown and it took me years to recover. But when I hear the song "Amazed" by Lonestar, I remember the good times we shared before the bad times.
As for my ex-wife, it's hard to list a single song because music was a big part of the good side of our relationship, but if I had to it would be "Slide" by the Goo Goo Dolls.
These are just some examples of what I'm talking about. In my mind, there is a song for each of the girls that I've loved over the years. And when I hear those songs or sing them, I remember them fondly.