I deactivated my Facebook account a while ago. It really was getting to me in the way you describe, far from feeling connected I was feeling disconnected by it.

How about you deactivate a while and see how you go? Deactivating freezes everything so it's exactly as you left it.

When I reactivated it I felt a better sense of perspective somehow and the overwhelming feeling was no longer there. I think I'll keep it as a contact directory but not look at it as much.