Anyone who is scared of diabetes is just someone who needs educating. You might find the people who are worried about it are the people who lost a great aunt (or whoever) to diabetes back when it was common for diabetics to lose legs, go blind etc. These days we can delay or totally avoid complications, we can even get a lot of them fixed up if we do get them. We can lead normal lives because we have the tools.
Perhaps some day there’ll be either a cure or even better tools… til then, people will remember diabetes’ bad reputation and be worried.
But all they need is a little education!
Anyway, I don’t think this applies to that many people… most people are totally ignorant about it and have no reason to be worried!
All in all, when you meet someone, what they should be interested in is YOU. The fact that you have to think twice about eating stuff shouldn’t be any different than the fact that they have cold feet, or take a pill for something, or are allergic to something etc etc.
D really isn’t that big a deal when it comes to romance 
Set yourself free!