Yes. If you have diabetes type 2, you can have some control over that. Losing weight really helps. Changing diet is very important. That is mostly accomplished through what we eat and then exercise has great benefit as well. More information would be helpful. :>)
The treatment is totally depend on what type of diabetes you have. If it is type 1 then it is not treatable, for that consult your doctor and follow the treatment. But in case of type 2 diabetes, there is chances of getting control over it. Also regular exercise is the most important to maintain healthy sugar level.
This depends on whether it's Type I or Type II, and if the latter, how far the disease has progressed. If it's Type I, there's no cure and you have to do what your docs and nutritionists tell you to do. Type II is more of a lifestyle disease, as long as it hasn't progressed so far that it becomes almost impossible to separate from Type I. What type do you have? And by the way, when you say no carbs, this is a frequent misinterpretation by people who don't know much about nutrition. The most important foods to eat are carbs, as this category includes all the antioxidant and nutrient dense veggies. Certain carbs that metabolize quickly into sugar should be avoided, but the healthiest diets will be heavy on carbs.