Do you think when one writes about despair that he reinforces this feeling or catharcizes himself of it?

I'm pretty sure "catharcizes" isn't a word...but I know what you mean. Anyway, I think it would depend on the individual. I like to write and I write really depressing stories sometimes, and for me it doesn't seem to make me more sad or less sad - pretty much I just stay the same mood as before, except sometimes I will be slightly cheered up if I think it's a really good story. (That has more to do with narcissism than catharsis, but still.) It's just nice to feel like at least *something* good is coming out of all my bad experiences... On the other hand, my writing might have longer-term adverse effects on my mood...such as due to self-perception theory, over-ysis, dwelling on the past, or whatnot. (That never occurred to me until now.) Even if that's the case, though, I'm not going to stop writing. For me, it's worth it.