Boyfriend eats way too much!

Yesterday I bought 4 pounds of meat that I was planning for us to eat and was thinking it's great because it will make a few meals. So I open the fridge today and it's gone and he tells me he ate it. All of it. In two servings. Not including the potatoes and sauce he had to go with it. I told him that's a crazy amount to eat and it's not healthy and it's definitely not good for our already strained economy. He always does this. And it's so hard to talk to him about it because he's a big guy and has gone up two sizes as well since we met (6 years ago).

Whenever I try bringing up eating healthy he gets so defensive. He's got both diabetes and heart problems in his family and we have a child together. It's so frustrating! I love him and I dont care about how his body looks, but I want him to be healthy so we can be together until we're old. What do I do? Also he always says he's going to eat healthier, but that always ends up with him going "keto", meaning his portions only consists of 2 pounds of meat. That's definitely not what people mean when they say it's good cutting out carbs!

I try so hard to be supportive, but it's like he's trying to do the most unhealthy choices possible. So far I've tried talking about it (he just gets upset), encouraging him (no effect), tried making healthy meals (but then he just cooks another huge piece of meat for himself to go with it so it gets undone), I served food on smaller plates (he just ended up getting the bigger plates for himself), encouraged working out (he refuse to come with me everytime I ask him). I even had his mom talk to him about it and he cut her out of his life for trying to help him. I'm at loss. I can't force him to want to change himself, I know that. I just need help.