Fitness plan symptoms and conditions

I am 25 and I have a severe case of Ulcerative Colitis. I have been taking Prednisone for about ten months, about as soon as my little daughter was born I started taking it, and I have gained about fifty pounds. I am so depressed because before I was pregnant I had just lost a whole bunch of weight and was very happy and healthy, and had just gotten married before I became pregnant. Things were going great. Now I don't even want to leave my house because I don't want people to see me. I feel like a balloon. If I am able to stop the medication, will the weight gain stop and will some of the weight I have gained go away on its own or am I going to have to get working on a fitness plan again, because I am still pretty ill and it is difficult for me to work out. Help! I am so frustrated and I don't know what to do.