I do not have coeliac disease, although I've been tested several times. I am intolerant of wheat, though my reactions to wheat have calmed down considerably recently.
Years back, it was far more difficult to avoid wheat products and I had to avoid processed food, but now there is far more awareness of dietary needs. There are far more free from foods on the shelves and ingredient lists have to be available in restaurants etc. There is far more awareness of cross contamination as well. But you do have to ask, but now I find that people usually fall over backwards to help you these days. There are a lot of excellent recipe books and you can adapt recipes. I experimented with different flours and use gram flour a lot for savoury dishes for example. By the way, I don't particularly enjoy cooking, but needs must. You get used to reading labels and recognising alternative names for ingredients that contain gluten, but now it's easier as it has to be highlighted.
Once you get over the shock and you start feeling better, it won't seem so huge, just a way of life. Coeliac disease is better understood by people than intolerance.
I've had both colonoscopies and endoscopies. I found the thought of both procedures far, far worse than the reality, particularly endoscopy. No horrid preparation for that!