Back in Zambia many months ago, Trevor and I attended a "close of service" conference to talk about post-Peace Corps life. We talked at excruciating length about reverse culture shock-- the notion that the adjustment to home can be much more difficult than going away in the first place.
Along with our absolute glee over being home, we have both experienced darker moments of melting down in the grocery store, momentarily forgetting which is the "right" side of the road, and missing our quiet routine, free time, and friends in Zambia.
Having adjusted to life in Zambia, we now see America with a much more critical eye. I'm especially having trouble with the way people here fritter away their time (Facebook!) and money, then complain about being broke and overbooked.
The upside is using this information to make better decisions about how to craft our own new/old lives. And lots of practice in keeping our big mouths shut!