I have the strangest memory. I can remember facts, theorems, and all sorts of things that are easy to reason about, but my experiential memory is crap. I find my friends talking about things we did together and I can't participate because I don't remember very well.

However, I'm beginning to suspect it's because I spend too much time thinking to myself and not enough time paying attention to the outside world. Does anyone else have a similar experience?

Yes, and I feel the more I get into programming and reading the worse my social memory gets. I used to not read much in my lower teens but was more social. I would remember everything in conversation, exactly what happened, the clothes the person was wearing, just about everything to the point that it would make people angry that I would remember things that they wish I didn't. Now that I spend a majority of my time in front of the computer that ability seems to be fading. I think the brain restructures itself to handle memory that is related to the expected daily experiences, which would explain why the loner has a hard time comprehending or acting "normally" in social situations in their youth.

I've got a pretty similar memory. Can't remember events. To remedy this I try to keep a log of event(call it a diary if you will) so that I remember some important things I don't want to forget.

Have you noticed your experiential memory improving as you keep the log? I once kept a dream diary, and I started remembering my dreams really really well.