It probably is considered by most people to be odd, but I don't think it's entirely uncommon.

Interacting with people is exhausting. I know for me, I feel like I'm being constantly judged. I also cannot fathom why people would choose to spend time with me. I don't like myself very much so why on earth would they? And it's hard for me to build up the energy to appear normal, sociable and well-adjusted. As a result, I have very few friends because I just don't have the wherewithal to maintain most of those relationships.

Some people are just natural loners and there's nothing wrong with that.