Try to be calm...when I was first thought to have CFRD, I freaked out. I cried and cried, thought life was pretty much over. Then, they told me my sugars were normal again, and I didn't have to worry about CFRD. A year later, the same thing happened, but this time it was definite. CFRD was my new issue. Since I already went through the shock of having it, I was ok and just tried my best at learning how to deal with it...and it's not as hard as you think.
My dietician, endocrinologist, and CF doctor all told me that even though I was now diabetic, the last thing they wanted me to do was cut down on certain foods-especially if they're among my favorites. My dietician was even a little apprehensive when I started drinking diet sodas instead of sticking with regular, but I figured it was a better choice for my teeth if anything-plus I think diet tastes better now. CFRD is not like "normal" diabetes. Sure it's a good idea to keep an eye on what you eat now, but once you learn how your blood sugar responds to certain foods, it'll be a piece of cake (ha!) to cover whatever you want to eat or drink with insulin.
Once you get used to using insulin and learn your body's response to your CFRD, I would highly recommend looking into an insulin pump. You fill the pump with insulin and insert it into a site where it will stick for 2-3 days (it's a poke every 2-3 days as opposed to a poke 6-7 times a day). The insulin pump will dose insulin levels every hour, much like your pancreas. When it's time to eat, you tell your pump how many carbs you're eating, and it will do everything else for you. It's as simple as that. To me, my insulin pump makes it even easier to eat whatever the heck I want. It's extremely easy to use, too. If you can work a cell phone, you can work an insulin pump. I've had CFRD for 4 years and I've had my pump for 3.
You will be ok. It's not as scary as you think it is, and it's totally manageable! It just takes some adjusting at first. If you have other questions or want to talk, feel free to PM me!
Hope you feel better soon!