Hi there -
There are, of course, a number of possible causes of your symptoms, but one comes to mind right away, based on the whole story as you've provided it here: celiac disease. Not only are the symptoms consistent (although
nausea is a less common symptom), but also these symptoms seem to be influenced to some degree by the food you eat. Since celiac disease is caused by intolerance of certain foods (based on the presence of gluten in them), this seems a good starting point. It can be ruled in or out with a simple blood test, which could be done when you get yourself in to be seen by an MD, or perhaps referred to a GI specialist. If celiac disease is ruled in, dietary adjustment is the primary therapy and can be tremendously effective. If it is ruled out, then you may have somehow contracted a parasitical infection. I suspect this instead of a bacterial one because of the long run this problem has had at your expense. While
h. pylori could conceivably be responsible, the symptoms don't seem to match up as well for that as for some of the less obvious parasites, and they do tend to stay until they are forced to leave by appropriate medication.
The important thing is to get in and be worked up for this. It's got to be pretty miserable, and any of the possible causes could eventually make this get worse, and at best won't go away by themselves (which is pretty obvious by now anyway).
I hope this is helpful to you. Please update us, and also follow up as needed. Best of luck to you.