I have Crohns Disease and can totally relate to much of what you write here. It’s been ten years since I was diagnosed and I have come to a kind of negotiation with my body. I try not to focus too much on its negatives and weaknesses, I feed it carefully and well, I exercise (mainly strength training) when I can and rest when my body tells me I can’t. I try my best to keep my stress under control, be positive and calm. I take vitamin D in winter and have flu injections. In return my body gives me much more energy than it used to!!!