It's not fair, right? The struggle is hard enough even without additional obstacles. But we have to do what we have to do, and the playing field is never even, and some of us have to work harder.
I would just stop talking about this new lifestyle and focus on walking the walk for a while and see how it worked. I'd be watchful about what I put in my mouth but without the commentary (you say have not allowed him to change your choices yet - good!).
Looks like you are the one who cooks and shops for food - that gives you an advantage. Just calmly put on your plate only what you think should be there and don't allow yourself to be provoked or lassoed into a useless conversation about food. You have explained enough. When he puts something on your plate that should not be there - just leave it. Carry healthy things around with you so you can have them when you get hungry (and your willpower falters!) at the movies or wherever you are.
Just a thought.
A more serious consideration would be to look at similar behaviors in other parts of your life - is he trying to control other things? Does he try to restrict what you do? Why is he sabotaging something so obviously good for you? Do you feel angry, powerless or diminished by his behaviors? My musings might be a long stretch, brought by memories of workplace abuse I long ago experienced, but what you described got me thinking...