I had to go on a diabetes diet for gestational diabetes and it was GREAT! I was about 15 lbs overweight, and didn't gain too much while pregnant. Of course, temptation got me after the baby was born and I went off the diet (SIGH!)
Anyway - the key was balancing protein/fats, carbs, and vegetables, and not having more than 2 servings of carbs with each meal (30 grams). Also, attention to portion size (palm of your hand for most things) was important. You can eat ANYTHING on this diet, if you eat it the right way - example - I had CHILI FRIES!!! just a smaller portion - fries/carbs, chili/veggies & protein. Super tasty. Had a salad with it and voila!
Also, on this diet you ate 6 TIMES per day. Breakfast, snack about 2 hours later, lunch, snack, dinner, snack. Snacks were also protein/carb combo for energy and balanced sugar intake.
You might be able to find something at your library or online to use as a guideline. Good luck!