What I suggest is to try whatever you think helpful. Your reaction is pretty normal. Friends of mine always tell me to be positive, but keeping a positive attitude is not easy. When you are in down mood, do not be bothered by "why am I so scared".
This sickness is often thought of as a minor problem by those who are healthy. Everyone here may know how tough it is to cope with all the inconveniences brought by UC. It would be great to find something that helps you maintain remission forever. Even not, a life change may let you feel better.