Sounds like he wants to eat what he wants to eat. And you NEED to eat healthier. And you are doing the cooking.
There are a few ways to tackle this:
You can make him big batches of food, and he can reheat as required (i.e. stews, etc.) and you make your own food.
You can cook more WW recipes that you both eat in order to cut your work down, but stick to the one serving. (the problem with you eating 2 servings is really your issue, not a result of HIM...)
You can cook your own food, and he can cook for himself...
Other than that, he's going to do what he likes. You can have him try foods, but you can't change what he's going to do. The key is to find a solution that works for YOU...
Kira
ps. There may be more to this than the food -- the food may be a symptom of something else: is he insecure if you lose weight? is he not supportive of a separate identity for you? Just asking...