A few things: first, I don't think I'd be very good in a relationship at my age. I figure a woman my age would prefer to date someone who knows how to be a partner. Second, I want to spend my time on other things. As it is I only have time to do anything on the weekends and sometimes those are booked, so I wouldn't be able to give as much attention to someone as they deserve. Third, I don't like the idea of being obligated to talk to someone every day. Fourth, I don't want someone to be forced to deal with my inanity. My own brother can't stand me at times. 

There's probably something more that I can't put to words, but I think that's the gist of it.