I can completely relate. Everything seems like a chore when I'm depressed. I've been in your shoes before where there's things expected of me, although not required, whether it's work-related or another obligation/invitation.Countless amounts of times I've ducked out of things. Sometimes I'll make excuses to get out of things. I do realize that depression is what interferes with following through. Even when manic, I'm flighty, so my motivation isn't on the "important" things.

You have very valid reasons to feeling the way you do. It sounds like a real pain to go to this conference. However, I do think of times I've forced myself to go to places, and it ended up not being that bad. Maybe that's something to think about when making a decision? Sometimes I give myself a little push when it comes to certain things. If you aren't feeling up to it though, then at least it isn't a requirement, making the situation less pressure than it would be otherwise.