It's an inescapable fact of AIDS/LifeCycle: Our seven days on the road are an all-consuming escape from reality that tests our physical and mental limits in ways we never thought possible. We see humanity at its best, and we grow accustomed to it.
Then we have to return to the real world.
Especially for first-year riders (and for the rest of us, too), that return to reality can be an incredible letdown. The effects, not surprisingly, can be both mental and physical -- depression, weight gain, irritability, just to name a few.
Part of the preparation for ALC is taking steps before the event to mitigate those aftereffects. Plan activities with friends. Schedule some light physical activity. Set aside some time for yourself, doing some activity that you've had to curtail due to all those training hours. Have this in place before you begin the ride so that you won't have to arrange it in a hurry when you get back.
Yes, we take the lessons of ALC into our world, but the days immediately after the ride can be a very vulnerable time for us. Realize it, embrace it, and conquer it.