Sometimes symptoms happen regardless of what we eat. It may be that the improvements you can make with diet are limited. The safest diets, the ones easiest on the digestive system, are enteral nurtrition or a liquid diet. You'd need to speak to your doctors about them, though you could try a couple of days liquid diet without medical supervision. Low fibre, soft foods are the safest solid foods. But it may be that you need to focus more on mediication and other treatments. If you can get your disease in a better state, eating may not cause such bad reactions.
Keeping a food and symptom diary can be more complicated than it seems. You react to quantities as well as types of food, and the time for reactions to occur can vary greatly. If you're not able to see trigger foods don't get stressed by it, just tell your doctors it's not working for you. It doesn't help everyone so they should understand and concentrate on other ways to help you.
Mind you don't develop a phobia of food. It's easy to become afraid of eating but you need nutrition, and if you're not absorbing everything, which is a possibility, it's important to eat more if you can. Try eating calorie-dense foods so you don't need to eat a large volume of food, and drink plenty of high-calorie drinks. It may feel worse in the short term but malnutrition can cause health problems too.
