I have not had MDS, but it is a very serious disease. And it takes your autoimmune system months to rebuild itself. I watch myself pretty careful to make sure I don't over do it or am exposed to people and situations that can make me ill.
I still do things I enjoy, but try not to over do it. I take Pilates but went down from 2-3 classes a week to 1 private session a week, that is geared to where I am on the day I show up. I read, I watch movies - via stream or DVD. I see friends - but only a few at a time. etc.
I have some friends that I barely see or speak to since my diagnosis, they just don't get it, how tired I am, how much time I need to spend with appointments, etc. I decided to stay with those who were positive and supportive, and deal with the rest as little as possible.