When I get sores through my GI or stomach and they start to bleed - tried a lot of things - usually do the "bowl of cereal diet" for a few days while I take supplements. It's kinda like a liquid diet. I know it sounds stupid but it works (corn only though - not wheat). I've tried a wide variety of shakes, Vega, Garden of LIfe, goat milk whey, egg protein, Soylent, Soy Isolate, Muscle Milk, Biochem, Slim Fast, Medifast I think it was called -- so lots of different things. The winner probably was Biochem Whey and the cereal diet.
When my GI is really a mess I can't tolerate much food.
Supplements I use: L-Glutamine, Intestinew, Aloe Vera Gel Caps, and Slippery Elm.
Good luck in your liquidy quest!