In my life, other than the sole exception of my desire for a girlfriend, I am absolutely indifferent to other people. I don't have friends, but I'm not a lonely person, nor am I shy or inhibited. It's more like I lack a "social drive"; I don't experience a need to "belong".
Often for purpose of work and other functional areas of life, I have to feign an interest in people and put on the impression of a more gregarious person. If I didn't have to work, I think I'd pretty much be a 24/7 hermit.
I should note that I didn't have any friends while growing up, so I've really only ever been a loner. Yet, most people in this predicament often are seriously lonely or otherwise have major emotional problems, but this seems to be absent from me.
In fact, i'd dare say it would be good if more solitary people were like you.