Jo,
It is a scarey day when the docs say you have another major illness on top of CF. When I was 27 I was diagnosed with diabetes.
The two things that helped me to manage it, and also learn about it was meeting with a good endrocronolgist. But be sure the are familiar with CFRD...... sometimes they will try to treat you like any other diabetes patient and want to limit fat intake and sugar intake. With CF, these are no the way to go.To control blood sugars, with CF, dosing with insulin with each meal, and counting carbs is the preferred way. This allows you to take in the amount of calories and fat you need. Diet control is not something a CF doctor wants you doing.
Ask to meet with a dietician too. They can help you get some plan in place for eating well and getting the correct fat and calorie intake. I know when I was diagnosed and learned what foods had sugar and carbs, I was shocked. Bananas were amazingly high in sugar.... they appeared to be pretty innocent. Just like potatoes and rice. They seem to be innocent, but the starch, carb content is high. You learn a great deal about food when you become diabetic... and that is not a bad thing.
Good luck.
Joanne Schum