I too had gi issues undiagnosed for 27yrs, accompanied with severe abdominal pain. Finally at age 49(things started age 22), I went to a gynecologist and he discovered a large ovarian cyst that turned out to be endometriosis. It was everywhere, including on my intestines and bladder. That was why I was having problems. At same time it was discovered that I am gluten sensitive (common with endometriosis). Have you tried a gynecologist?