I believe that "normal" people may compartmentalize memories more "logically", by future plans and things they need to remember, while we compartmentalize more by emotions and our senses. A song or a texture can send me back 20 years due to the emotions of the time. I instantly feel the emotions all over again...they don't appear to have diminished over time at all. Other's brains automatically detach most memories from the emotions in short order. That is probably why abandonment is such a big deal for us as well. Everytime I see certain things or go to certain places, I'm automatically taken back, the emotions are still as strong as ever, and the abandonment feelings start all over again. My best friend broke up with me 15 years ago, but everytime I hear certain songs, it's like it just happened and i sometimes make the stupid mistake of trying to make up.... And you're right....we don't forget.