Oliver,
I thought it would be helpful to offer my opinion/insight. As the others have said it can be a game changer. I think its important to understand that unlike Collitus this is not a cure for Crohn's. I can only imagine but it sounds similar to my journey. I have never been able to find remission, have been through all the meds from anti-inflamitories, pred., remicade, humira, and entivio, all with at best being able to barely function. Like you said its like being prisoner in your own body.
I decided after my last major bout of perianal abscesses/fistulas which I had for 10 yrs. after my first resection it is time for something else, because living that way was not really living. They removed 2/3 of my large intestine and a foot of my small my first surgery, with no bag. I didn't have any remission which is usually typical after surgery, at least for a few years. In May of this year after thinking about it for a over a year I had a total protocolectomy. I thought I was well informed about what it would be like to just have a bag, but even I have still gone through the post op. ups and downs. Did I make the right choice, will there be issues with body image, and so on. There is definitely a new learning curve, but with guidance from professionals finding the right equipment can be achieved, but seems overwhelming to start. Any public bathroom situation you are already a pro with crohns so that adjustment isn't such a big stretch, plus you may end up using the bathrm. less. I went from 20-30 times a day to 6-8 empties, and that alone has been a game changer for me. I used to have accidents and so far with the new equipment I have not had any major malfunctions. All my fistulas have basically completely healed. The other things you should look into are what you will need to now about how the equipment works, the preparation and protection of your skin which people do have problems with. Aside from the obvious irritation you can get, there are other possible manifestations of the illness on the skin. I am still at the beginning of what you are thinking about going through and as of know I would say it was and is for the best. It is a major decision and no matter how much you learn before hand it will still be a change. I will tell you that I now have space in my brain for life instead of where is the bathroom, will I make it, etc. etc. I haven't let it stop me from doing anything I want to do, the exact opposite, so much more freedom. People I know have said I look so much better, my color has come back and I don't look sickly like before. I don't want to write a book so...........
Discuss it with your doctors ask all the questions you need to. Ask questions to people like me and the others who have gone through it. If you are that sick it may be a great thing, but surgery is usually a last resort, and by that I mean to save your life in an emergency or to save your life by giving your life back. If you have any specific questions send a message. Hope you find the answers and your way through it. Good luck.