I know many people and different professionals would argue with what I'm about to say, but I stay angry. Not angry at people or myself of course, but angry with being sick. I also don't balk at being angry with dismissive doctors and health care system based more on cost effectiveness profits. I do not find this type of anger draining (not too much at least!) I find it allows me hope for there one day being a cure for autoimmune diseases and then a way to prevent them before they ever happen.
Don't get me wrong, in the middle of a flare-up or after running out of energy 5 minutes after my day starts, I can get very depressed and down on myself. I try to avoid that though because I've seen what that whole depression, lack of sleep, increased pain and loss of appetite cycle can be like with me. I need more problems wth those 4 factors, like i need another autoimmune disease!