Who knows, maybe it's part of the the low-level threat scanning aspect of our nature. Maybe it has something to do with our capacity for self-consciousness, maybe it's a side effect of being sentient.

I somehow doubt that it's a purely socially ingrained tendency though.

Maybe its more conditioned than an evolutionary thing? We've all been barraged with media and social interaction 16 hours a day for most of our lives and most of us never stop thinking all day, and even dream much of the night.

Amusing. Guess its how 'being socially engaged' has evolved.

It wouldn't surprise me if many of us develop similar traits of isolation even when cut off from internet too not just physical interaction.