Not surprised about your doctors' or nurses' reactions, i.e. it is not uncommon at all, indeed quite common. If it's not "oh, because you are a diabetic", it might be something similar and equally banal and stupid, like "oh, it's your age" or "you're never going to get BGs down to 47-48 (Hba1C)", etc. I'm afraid primary healthcare provision (i.e. that afforded by doctors and nurses at GP surgeries) is often quite useless and you find that you as a patient can know far more than them about an individual condition through wide reading, even though the secondary provision (i.e. that available and given in hospitals) is usually, though not always, excellent. The moral of the story is that, for one's own health and life, it's best to take the matter in one's own hands, equip oneself with as much knowledge and understanding as possible, and question what the frontline medical profession (in surgeries rather than in hospitals) is spouting rather than take it as gospel and put your health in jeopardy. At least that is my personal view from experience.