Gerd, the extreme fatigue is exactly what Addison’s Disease does. The only way to clear it up is to get adequate treatment. If you can’t take the medicine for some reason it’s important to contact your doctor to discuss alternatives. Addison’s disease can kill you if it’s not treated properly.
I’m not sure how the pouchitis diagnosis was made, but it’s possible that it was incorrect. Antibiotics will reduce stool frequency for most people, whether they have pouchitis or not. My suspicion is that you may have cuffitis, and it could easily clear up once your steroid dose is adequate.
I’m not sure what your stress question is, but I don’t think stress is causing any of the problems you have described. Good luck!