When I was younger, I was incredibly social. I would talk to anyone and everyone, and try to make as many friends as possible. I just loved getting to talk to others, to get to know them. Then, when I entered high school, everyone I knew just started drifting away. They started playing football, basketball, some became cheerleaders, and others just lost interest. I found that I was also losing any desire to talk with them, so maybe it was my fault?
I actually found two of my closest friends in my high school years, both of which are otaku. I guess I just lost any desire to talk to people who are too different from me.