Molly
Your mother needs to see someone who specializes in gastroenterology. She may have Crones disease, ulcerative colitis, trouble with her pancreas. I am sure there are a lot of other disorders that could be causing her symptoms, that I am unaware of. In any case she should likely be seeing a nutritionis to make sure that all of her nutritional needs are taken care of. I have had friends who have not been able to eat regular food for as long as 6 months and doctors are very worried that they are taken in the proper nourishment. Determining the cause is the most important step, making sure the patient is nourished is second and then start determining if there is a solution. The solutions and diets vary depending upons the cause. Keep after your mother to find some answers and seek another opinion or get a referral to a major medical center if necessary. Good luck.