So sorry to hear you're stuggling with gastritis on top of all your other issues. I have a very reactive stomach and react to antibiotics, and of course anti-inflammatories.
The fact that you have GERD as well, complicates things futher. In my experience (before my Nissen fundoplication to stop reflux) whenever I got gastritis I'd get terrible esophagitis from the reflux. These would take me at least 2 months to heal and get feeling better, and I'd lose 20 pounds each episode because I couldn't eat.
Try egg custard (find a recipe online)...it's got lots of nutrients and is smooth, so it won't irriate your stomach or esophagus.
Carafate suspension...it's a prescription drug, but very benign. I have been told by my PCP that it is totally safe to take long-term. Most is just excreted in the GI tract. It's a liquid that was developed to protect healing ulcers. It coats the esophagus and stomach and protects them, so they can heal. I found immediate relief. It lasts much longer than Maalox-type liquid antacids. It's not an antacid...just a protective coating. Each dose lasts about 6 hours. You could ask your doctor...
(Only problem...you have to take in an hour before or two hours after eating, and 2 hours before or after taking other medications--because it'll inhibit absorption of the meds)
Don't eat anything that can't be chewed to a completely smooth/liquid consistency, because it will irritate your esophagus and stomach (when it mashes the food).
Wish I could be more help.
Hang in there!
Words of wisdom by Eckhart Tolle:
"Whatever you fight, you strengthen, and what you resist, persists.”
“Worry pretends to be necessary but serves no useful purpose”
“Accept - then act. Whatever the present moment contains, accept it as if you had chosen it. Always work with it, not against it.”