It only seems like you had to buy twice as much food. The thing is, your household is eating 1/2 as much sugar and grains. After a while you will see you aren't buying rice and bread very often. And if you're not eating cookies and ice cream, let him go to the store for that.
However, you are perhaps buying more fresh vegetables and higher-quality meat. That's where the real expense is, and you know you should have been eating more vegetables all along anyway.
After a while you'll see that you'll figure out enough simple recipes that both of you can enjoy. My sugar/grain-loving man tends to like things that are served over a big pile of rice or pasta or wrapped in tortillas. No big deal. Rice, pasta and tortillas are cheap. I'll just pour my stuff into a bowl, over lettuce, over a sweet potato or whatever and he can have all the rice, pasta and tortillas he wants. Sometimes I have the rice myself, too.
Female, 5'3", 48, Starting weight: 163lbs. Current weight: 135.
Starting squat: 45lbs. Current squat: 145 x 4.