I see a lot of comments here along the lines of "I prefer to live alone because roommates are a pain in the ass", but I think there might be a lot of value to doing this because it's good for you. Living with other people forces us to corral our worst tendencies, to break out of virtual worlds to engage in the real one, to form bonds that will force us to grow and change.
I think it's strange that our preference in this area, but not many others, could be so dominant over what is good for us.