I'm reading God's Debris (you can freely download it from http://www.andrewsmcmeel.com/godsdebris/) for a second time. I must have skimmed through some of it during my first reading, because I don't remember reading this one amazing chapter on relationships.
First of all, the book is actually billed as a thought experiment—the reader is supposed to discuss what's wrong with the arguments presented in the book with a friend.
With that out of the way, I still think that book's chapter on relationships might be a good starting point for an explanation of why I, to put it bluntly, don't have a girlfriend, and tend to be a social hermit sometimes.
One of the main arguments starts by breaking the population down into two different types of people, idea persons and people persons. Since people tend to "light up" when the conversations focuses on them and how they would react to certain situations and other aspects of themselves, people persons tend to form interpersonal relationships more often than idea people. I mean, a conversation about that new tool you found at the hardware store eventually gets boring and dies. Needless to say, I'm an "idea person", that fits me to a tee, and it would probably do me some good to focus on people every once in a while.
dsevil