When I am flaring I do my white food diet. Of course, you may have to adjust for the celiac. I eat fish, chicken, eggs, rice, potato, pasta, bread, custard, puddings, yogurt, tapioca, cheese. Basically bland, soft food that has some nutrition but little to no fiber.
C-Diff is an infection caused by antibiotics
you need a detoxifying diet. Try the maker's diet.
It's eating only natural foods like fruits, veggies, meats, fish, whole grain sourdough breads, plain yogurt with probiotics, organic cheeses.
Cut out all sugar, white flours, and everything else processed. This feeds the bad bacteria and it's bad, in general.