Unfortunately your situation is very common. The good news is that people can change, if given the rig stimulus. I speak as someone that was doing to my wife, what your husband is doing to you. I didn't see a way out, so I didn't try. I will give you my experience, and hopefully help to provide a solution.
As a child, my type 1 diabetes control was fantastic. My parents decided everything for me, so I ate healthily. I became a teenager, and got much more independence. My control went to hell. My worst HBA1C was 10.4. My parents and doctors lost patience with me. They were right to tell me off, but I did not see it that way. I was starving all the time, and didn't think I could change. So I had arguments. I falsified my blood sugar results, and stubbornly said the HBA1C was a stupid test because I was clearly in control. Reaching adulthood, I made more of an effort, but not much. My HBA1C was in the high 6s usually. However, this was because I was having loads of highs and lows. I tried to change. It didn't work because I was not making a proper effort. But I lied to myself and told me I was doing everything in my power. When my girlfriend (now my wife) made a suggestion, I would get angry. What did she know? I had been living with this for decades, who was she to come in and talk about things she didn't understand. The moment she wanted to discuss diabetes, I felt like I was back in diabetic clinic, my DSN telling me off.
Please do not misunderstand me here. All of these thoughts I was having were wrong.
What I failed to understand was that when you are in a relationship, your partner inherits your problems as well as your good points. When I had a hypo, my wife had to deal with it. If I damaged my body, she would have to watch me slowly fall apart over a few short years. Once I realised this, I started to listen to her. I was shocked to find that she
could help. Suddenly, I realised she was not ever telling me off for my poor control. She was saying 'there is a problem here, how can we fix it?'
Just over a year ago, I started engaging with her about my diabetes. I admitted I was not fine. And it felt amazing. I thought I was protecting my wife by not talking about my problems. In fact, I was failing to hide that something was wrong. Once that was out of the way, we went from strength to strength. We monitored my results, and found that things seriously needed to change. We tried all sorts of things, and we're not seeing any success to begin with.
Then I found out about a different way of eating. I came across a book by a man called Dr Richard Bernstein. He is a type 1 diabetic diagnosed as a child. He is now in his 80s and is in excellent health. He advocates eating a low carbohydrate diet to manage diabetes effectively. I was extremely reluctant to try it. But I thought I would have a go, and see what happened.
The results have been revolutionary for me. I have been following a low carbohydrate diet since January, and I love it. The crippling hunger I had all the time is gone. I don't have many hypos, and they are so much more manageable when I do. I used to think if I was 12.5 that was an ok result. Now I see anything over 7.8 as unacceptable, because I can so easily avoid that.
So the big question; how can you persuade your husband to change? I guarantee he is terrified of the future, and is coping with denial. He is lashing out in frustration, which is the worst thing he can do. You do not deserve this treatment. He doesn't know it, but he needs you. He can't win against diabetes without you. But he has to put the effort in too. My suggestion is to sit him down, and discuss the following points.
Your husband dreads thinking about diabetes.
He does not want to show you his blood sugar results. They are the best he can do, and he is ashamed of this.
You want to understand more about diabetes, and you need his help to do this.
Then, I would suggest showing him the following video. You could even skip everything else, and just ask him to watch this. Tell him it would be an amazing Christmas present if he did.
Important point, that should be a link to a talk given by a man called Dr Troy Stapleton. Someone followed it once, and for some reason it took them to a site claiming it could cure diabetes (I am definitely not claiming that's possible). If in doubt, search youtube for Dr troy Stapleton, the best video has pictures of food when you find it. Have a watch, and if you agree with what's said, show it to your husband. I believe this way of eating has saved my life.