Hey there, Nanners and FitzyK23 said it well, very well. It is very dependent on the course of your disease. Also how you handle the disease process emotionally has a lot to do with working.
I know some people that have been on disability almost from the beginning of their disease and others who worked whenever they could. We know that Crohn's can cause severe pain too so again it is an individual case by case decision.
I hope you will continue to work as you have the desire too, that is half the battle. :)
Take care and keep posting.
I had one other thought for you. When the time comes to tell your new boss, maybe you can print off a copy of the article that "climbs" recently posted/wrote that was on the online Newsweek site. I printed it off and shared it with alot of my co-workers and got alot of excellent feedback from them. It really helped them to understand what I go thru daily. Just a thought!