@Vicky1967, I truly feel for you. I've read through all the comments including yours and agree - you must take care of yourself and your daughter.
It is unbearable to think of life without someone who is harming himself, especially through carelessness and stubbornness. I know: I live with a man who has been hypoglycemic all his life (as was his father). I keep trying to modify his diet to reduce his carb intake to prevent him from going hyperglycemic and full blown diabetes (as his father has done).
I am a type 1 diabetic (48 years!) and I know what it's like to ignore your diabetes. I have days when I feel it's just too much, too hard - but those days are now few and far between. How? Because I feel awful when my blood sugar is high! My temper is shorter and Everything. Is. So. Hard. I'm thirsty and peeing like a racehorse at every turn. It took me a very long time to get over my diabetic grief (yes, that's actually a thing) and learn to live without going wild.
One thing that helped me was to set a "be bad day." If I went all week and was very good, I let myself have a piece of cheesecake on Friday. The hardest part of this, though, and the thing you'll find is the most troubling for your mister is you must be honest with yourself.
You can't set the goal for him; it's got to come from him. Look at it this way: People don't argue with their own data. While you're around him and he's being good, ask him how he feels. When he's eating like there's no tomorrow, ask him if he's thirsty or sweetly point out how many times he's gone pee. HE needs to make the connection, though. The more you point it out, the easier it is for him to identify YOU as the problem, not his behavior.
Be ready to accept that he may never accept his disease. He really doesn't have to - I fight mine all the time! But living on the low carb, I feel so much better! I can still fight the disease and hate the disease and treat myself well.
Lastly, one analogy I told my stepmother-in-law to help her understand my situation (and stop offering me sweets) was that she could think of me like an alcoholic. You wouldn't offer a recovering alcoholic a drink, would you? Well, my alcohol is sugar. Don;t offer me sugar. It finally helped her understand.
I wish you all the best, my friend, and I will keep you and your family in my prayers tonight.