This is textbook major depressive disorder. I know you probably don't want to hear that, but you're basically describing a classic case of depressive symptoms.
> Employment is secondary, and it follows from having a social network and being embedded in a social context.
I'm sorry, but viewing these two things as connected or expecting one to follow the other isn't helpful. We all need a social life and we all need employment, but tying the two of those together isn't healthy. It's important to have a social life outside of work. It's important to have a job that isn't equivalent to your social life.