Someone who obsessively seeks out social interaction at every available opportunity.
Someone who can't stand their own company.

When you eat dirt for the first time and leave your family to build a shack in the woods

A person that is so absorbed in others, yet in such a shallow manner as to mimic social networks, so that the person never knows a person as a human, but as a username.

These people tend to be vindictive and rarely move from their friend groups. They seem to think on a 2 dimensional plane similar to the Internet encounters: like and dislike.

Sociophiles have a knack for stirring up drama.