You know you're diabetic when you go with your husband to what was your favorite restaurant, and realize that there is nothing there you can eat anymore. (and he still likes it).
...When you start injecting your lunchtime bolus at work right there in the office you share with 2 guys (instead of going to the bathroom to do it).
...When everyone asks you what diet you're on that you managed to lose so much weight, and you explain that you were diagnosed with diabetes and are eating very low carb, and each one says, "I couldn't do that. I MUST eat bread"