Yup, I have Ulcerative Colitis but it has been quiescent for around four years. It arose a couple of months after the diabetes started 25 years ago.
I don’t eat any special diets, other than avoiding high insoluble fibre foods. In fact, I only tend to get flare ups if I stop consuming nicotine, formerly if I stopped smoking my pipe, and now if I stop vaping. So I continue to vape, and eat whatever I like, Indian, Chinese, Thai, Italian and British, all made at home rather than takeaways, then I know the carb value.
My diet is complicated by my Chronic Pancreatitis ( there is an association with UC) which means I have to take digestive enzymes in the form of Creon capsules with meals.
All these are minor inconveniences. Including the diabetes, which is well controlled. Or certainly the least of my health problems, but that’s another story.