An epiphany of sorts while reading Wendell Berry (whose writings are good for these sorts of things)...
There is one reason, and to my thinking, one reason alone why it is so hard for most of us to feel a real sense of community in our church, neighborhood, and among our circle of friends.
We don't need each other.
All of our various needs and wants can be supplied almost entirely by ourselves or through the agency of complete strangers. The internet even allows us a certain sense of companionship to be delivered wholly at our discretion, we can flit in and out of various on-line "communities" as we see fit.
One of the over-arching themes one finds in Mr. Berry's work is the manner in which the people of the community of Port William are truly members, each one an integral part of a greater whole. The roles change as people become elderly, or die, and new members attain adulthood to take their place (or not in the thread of sorrow that runs through his work), but the subtle interplay of strength, ability, and personality is always there.
Most modern communities, even "intentional" ones, do not and cannot have such a bond, because in most cases the bond is entirely voluntary, severable at will, or worse yet, an affectation.
What is needed is not a voluntary simplicity movement, but an involuntary weakness, a shedding of those things that make us independent and free, in order that we might learn what it is like to rely on others for our very existence. There would be, I think, also a grace found in relying on each other, with our failures and imperfections that is not found in the relatively seamless functioning of our interactions with modern industrial society.