So basically what I tend to stick to is very simple, healthy stuff. Granted we all splurge every once in a while on stupid stuff we shouldn't eat (for example I have a supplement I can take if I want to eat a sandwich and can't get a gluten free option at a restaurant or whatever but it's really expensive and I use it sparingly), but usually my days look something like this:
Oatmeal (gluten free) with a serving of fresh fruit for flavor, usually stawberries or blueberries. If I have anything to drink it will usually be water or tea.
If I need a switch from oatmeal I will eat usually scrambled eggs with some kind of veggie and some potatoes so I don't start losing a bunch of weight, which has been an issue in the past.
This varies but usually a green salad with veggies and fruit mixed in for flavor (I don't really like salad dressing which is good since it usually has either a lot of fat or sugar if not both). I'll usually also eat some yogurt and fruit on the side.
Dinner is where I will eat my one and only serving of meat and I feel that it is hard on my stomach in general and I feel more sluggish when I eat it. But anyway, it's usually some kind of oily fish so I get my healthy fats (like salmon) or shrimp with rice or potatoes and a steamed vegetable, usually broccoli.
I try to stay away from processed foods and have set myself a ground rules of eating foods with only one ingredient, which usually means it's safe for my diet as long as that one ingredient isn't salt, sugar, wheat/gluten or some kind of fat. I don't really like dairy foods so I buy frozen yogurt (the refrigerated and frozen yogurts are the only real exceptions to my diet so that I get probiotics and calcium in my diet) and I snack on the yogurt and fruit throughout the day and I usually drink only water when I'm thirsty.
I also don't eat until I'm full because fullness makes me uncomfortable and causes me anxiety since I never know about my ulcers. Also, I don't eat past 6 (5 preferably) because I can't lay down within 2 hours of eating or my ulcers will perforate which is a medical emergency.