Well, I have never had this problem. I have found someone who accepts my diabetes and tries to learn more about it if there's something he does not understand. However, I was the one who was afraid that I may not be able to have children. We got married a little more than a year ago and to this day, my husband still encourages me that things will be ok and that I have nothing to worry about. That even if my sugars are fluctuating still, he will do all that he can to help keep me in control so that when we are ready to have children, we can do so healthily. His family is even encouraging and when cooking holiday meals, they keep my diabetes in mind, trying to make dishes low in sugar, carbs, fat, & sodium. (Sodium has nothing to do with it, but my husband & I both don't like salty foods.)
So, needless to say, I think that you just haven't found that "soul mate" yet. If someone really and truly loves you, they will accept you for who you are, everything that you are, and all your faults. Not only that, but they will let their family know and ask them to be just as encouraging to love you the way they love you because in the end, it would be a family's unconditional love to accept a "new" family member. Be patient, love will find you when you least expect it. Besides, you deserve so much better than someone who can so easily dismiss you for something that may just be but a small hurdle in a relationship, but nothing that cannot be jumped over and accomplished.
All the best with the new year!