Being diabetic since I was 3, and going through all that social fear (especially in school) associated with injecting in public, and worrying that I was being inappropriate injecting in public, whilst worrying about peoples reactions to it, having had a tough time in primary school.
This all impedes on your self-confidence, and un-rightly so! Growing in self-confidence and opening up with having diabetes in a manner that it is your condition that you deal with when, and how you wish, and expecting people to appreciate that has changed my own experience in diabetes, and since adopting this attitude I haven't experienced really any negative stigma with injecting in public, if anything, I have had people relate to me injecting (for example random people on the London tube). And the very few examples of negative responses, just ignoring the perpetrators as insensitive idiots. It can make someone really unhappy to have to shield their medication or health problem, and we really don't need that stress on top of managing our diabetes!