When I wrote about my experiences doing psychotherapy with people, one commenter wondered if I might be schizoid:

There are a lot of schizoid people in the rationalist community from what I can tell. The basis of schizoid is not all the big bad symptoms you might read about. There are high functioning people with personality disorders all the time who are complex, polite and philosophical.

You will never see this description because mental health industries center entirely around people Failing At Life, aka "low-functioning". As many radicals have noted, mental health tends to constitute itself mostly around "can't hold a job" or "can't hold a marriage".

The only thing you need to be schizoid is to dislike contact with other egos, and to shave off the experience of those other egos ruthlessly before they can reach the fantasy world you retreat to.