You should really work with your local Diabetes Educator and Registered Dietician to come up with an individualized plan.
I've worked in the world of diabetes for almost a decade, and the challenge with the disease is that it affects everyone differently and is progressive - meaning, it will continue to get worse as you age no matter how well you care for yourself. The pancreas simply begins to fail, and no medications/treatments available at this time have been proven (in humans) to stop that progression.
There are a lot of diets out there. But, there's nothing someone with Diabetes can't eat. Weight loss may not be related to what or how much you're eating either. It may be a mix of that, your medications, and your hormone levels (insulin, glucagon, amylin, GLP-1, leptin, ghrelin are just a few examples of hormones affecting weight).
Please see a Diabetes Educator and don't take our advice as the golden rule. Chances are, your insurance will cover the cost of the appointment, and they'll customize a meal plan based upon your weight loss goals, tell you how many carb exchanges you should have per meal (how many grams of carbs), etc.
There's good advice on sites like http://www.diabeteseducator.org/ and http://www.diabetes.org/
There are a few products FDA approved for Diabetes that have weight loss as a side effect by replacing hormones naturally deficient in people with Diabetes. It really depends on if you're type 1 or type 2, though.
Good luck.