Why is my stomach, small bowel and liver inflammed? I had my gallbladder and some liver removed in Mar 10?

I had my gallbladder removed as it had a large stone of bile which had turned to pus, also the gallbladder was attached to my liver by the lining of my stomach. Since the operation 9 mths ago, still unable to eat any fats, for instance ice cream, er, chocolate. Had various tests, but all come back ok, I am tired and have sores around my lips. Doctors unable to work out what is wrong.