Have you been tested for Gallstones at all? Pale fatty stools and bowel dysfunction/pain so bad you want to die are indicative of this. It sounds to me that this coupled with servere ibs (which fyi can be a severe systemic autoimmune condition and should not be undersetimated) could be your problem. Try a low fat diet with almost zero fibre fruit or veg. This may sound crazy and WILL constipate you but that can be relieved with stool softeners. I really feel for you and your frustration. X