I can empathize with the desire to be left alone.
Our true self is within, and by our thoughts, and being bold enough to confront them with logic rather than emotion, we can actually solve alot of our own problems.
Having people around is an influence on our thoughts, and so gets in the way of finding our true self. A self that is underneath all the 'effects' that have been layered onto it by a lifetime of 'lessons'.
How would our personality be different if we had never met anyone else?
It's interesting to wonder. We can best find out by being alone.
In reference to insanity:
The foundation of all mental illness is the unwillingness to experience legitimate suffering. - Carl Jung
ie: If the suffering is allowed to run it's course short term, it will be better for our sanity in the long term. (Logical thought will allow us to determine what is legitimate suffering and what is not...)
The distance between insanity and genius is measured only by success
-James Bond Villain 18