So here's the big question following from that (and I welcome responses from others with depression and others with depressed family members):

If I should see you in such a state, what should I do?
Ignore it? Try to pull you out of it? Option-the-third?

If I see you at home just repetitively playing Sims, should I kick you off the computer and make you do chores and get out in the sunshine, or should I just let you play computer games all day?

If I see you lumped in the halls at the con, should I leave you to mope, let you go home alone, or stick with you (dragging you to parties you're not in a mood for or following you home when I want to stay)?

None seem like good solutions. On the one hand, I don't want to fall into a parental-nagging role, but I also want to take care of you and help you get things done (and, selfishly, want things done around the house, too).

Answers from others who've experienced this situation (from either side) greatly appreciated. And it helps me to have these things written down rather than verbal and ephemeral.

Ian, I hope you don't mind me sidetracking your thread in this manner.