The cooks of this world want to not only make you happy by cooking for you, but their artistic sense compels them to want to control the menu.
So, there are a few strategies
1. Get her a low carb cookbook.
2. Print some of the low carb cookbooks on the Forum and share with the expert cook.
3. Practice saying, lovingly and gently: [Honey Bunch or other endearment], remember I can't have that?
4. Sorry, not on my diet.
5. Not this time.
6. I'd rather have a second helping of the [meat, veggies, nuts]
7. I'd rather have {water, tea without sugar}
8. You go ahead and enjoy that, I'll have [stuff on my low carb diet]
9. Precook your own meals, making her one two, in case.
10. Go shopping and get excited about the right kinds of ingredients.
11. Wow, I can only have 0% drinks. You go ahead and enjoy it.
12. Looks good but alas...
13. I need your help, dearest, could you make me this recipe?
14. Listen to things like Dr. Bernstein lectures together, read Diet Doctor and other such posts together.
15. (You know how you can lose some calories, distract at the same time, make someone feel cherished and wanted, all in the safety of your own home together)
16. It takes a while for people to adjust from the denial period into being a partner again.
Remember, your condition has changed the rules and needs in the relationship and changed her / him from of successful pleaser of yourself into someone who has to change, learn, adjust overnight in order to achieve the same.