Suggest Remedy For Pain Under Rib Cage

I have had more or less constant pain under my lower left rib cage for about 3 years. I had a lap nissan surgery in 1999 with complications and gall bladder removal the following year. In the last year the pain has become more constant but ramps up when i let my stomach become too empty rf when i eat grainy/fibrous foods. It also is more painful when i lie on my right side to sleep. i have had an MRI, an endoscopy, and a CAT scan within the 3 year time frame with no results: i am simply told they can find nothing wrong so there's nothing they can do for me. The two things that give some, though not complete, relief are pressing my hand into the painful area and opening a previcid capsule and taking the granules with water.