Just listen to you doctor and dietician, that is very important! What type of Diabetes have you? if you have type 2 you should probabaly loose some weight, if you already getting some antidiuretics you certainly be careful, because when the doctor subscribe you insuline, there is no way back. When the say you have to losse weight or take some diuretics, you can go back to a normal life without diabetes, but you have to work very hard to get there because you're a risk person. Do a lot of sports, eat the things that the dietician said to you and take care of your body.
I'm studying to become a dietician and this is one of the important things that we learn.