Welcome to Just Answer. I am confused about a number of things mentioned in your question. First of all, I wonder about why a nutritionist would be diagnosing a medical condition which is clearly way beyond their scope of practice, and why s/he would tell you to limit fruit and vegetables if you were gluten intolerant. Gluten is found only in certain cereal grains (barley, wheat, rye).
A healthy diet includes fresh fruits and vegetables, whole grains, lean protein and plenty of water within a number of calories that is equivalent to your body's exercise and metabolism expenditure. To lose weight, you must reduce the calorie intake and increase the exercise.
I would recommend you consult a gastroenterologist. First of all, you need to determine medically if you are gluten intolerant since that could affect your diet. A GI specialist is also the one to consult about the liver cysts. Cysts are ususally fluid filled sacs. Water weighs 8.4 lbs per gallon (2.1 lbs per quart) , so a 20-lb cyst would be the size of an 9-10 quart kettle, not a softball. Obviously someone has given you some very inaccurate information.
I hope all your medical treatment is being directed by your primary doctor who is ideally an internal medicine or general practitioner. They can help sort through and coordinate the information supplied by the specialists. If you have fibromyalgia, it can be treated. Likewise, adrenal fatigue can be treated. However, you need some coordinated care to determine what is wrong before any treatment can begin. Here are some general diet guidelines. Although they are specifically designed for diabetics, they are healthy plans that everyone can stick with for a lifetime.