Could be some lingering depression, or it could simply be a habit at this point. Do you drive him to school or leave the house at all? You could try not going right home - even if you take a laptop or something to a local coffee shop or somewhere. Just to get out of the pattern. The couch is too much of a temptation. Are you sleepy and not getting enough rest at night? That could be something completely unrelated like sleep apnea or something.

Try breaking the routine a bit. Get out of the house. Go for a walk, or to a park, even if you're just sitting on a bench people-watching. Eventually you'll probably find that you don't want to be on the couch much anymore.

If you still find yourself craving the extra sleep, talk to your doctor about a sleep study to find out how much rest you're actually getting at night.