Left sided, upper, under ribs pain

I have been having pain under the left lower ribs going into the back at times off and on for about 6 and 1/2 years.  Numerous tests, all coming back negative.  One Doctor did say he thought it was a sludgy gall bladder.  Current Doc says is muscular.  NSAIDS are not helping, narcotics mask the symptoms and thenI feel like crap the next day.  I do notice a worsening if I am a bit constipated, however, the pain does not go away with evacuating the bowel.  I do have a 40+ year history of HTN, elevated cholesterol.  I am a 57 year female.  Am sitting here with a pain level of 8-9.  Rarely goes to less than a 3.  Does make breathing difficult at times.  Walking does help some.  Am at wits end.  HELP!