jmb, I don't have a lot to say except, yes, I do think people get better. I can't say if it's because I HAVE to believe it or not, only that I do. I've been "cured" 4 or 5 times already. =)

About the sister's shower. Please don't take this the wrong way but KJ is totally right. Not worrying about it is the best thing, but part of the paranoia that accompanies depression makes it difficult to recognize how much or how little effect you have on people around you. In this case, it could be quite little. I've gone to parties, and on the way home, apologized for being morose, to which the response is usually "huh? didn't notice". Or, depending on the crowd, you could have the potential and do what you fear, so my advice would be, again, KJ's. Pretend you're having a good time, even if you aren't, and at least you won't feel meta-depression about being depressed. Will yourself into it and maybe it won't be better (it might, too), but you can say you did the right thing for your sister, and that feels _very_ good.

PM if you need to, and welcome. =)