This is SO like what my RB Smokey had 6 years ago. We did the same thing you're basically doing: gave her an antacid and feeding her tiny feedings almost like a kitten. Sometimes all you can do is treat the symptoms and hope for the best. Problems with eating can turn into an endless loop: they get off their feed, which messes up their liver, causing them to throw up, which makes them EVEN LESS wanting to eat. Anything that can break that cycle, like we did with Smokey may help.

Good luck, and {{hugz}} to you and Pepper.