Regarding your food addiction, I guess it depends where it's coming from for you. Sometimes it stems from boredom, just something to do while watching netflix or whatever. Other times, it's to get a quick dose of happiness for whatever reason. Then there's also those of us that actually really love good food.

For the first case, I think it's relatively easy to counteract weight gain from grazing. Just change what you happen to be munching on. For myself, I've found fresh snap peas are amazing for this. They are ridiculously healthy, tasty, and it can take half an hour to consume a bowl of them.

Similarly, if you want a healthy treat as a dessert, try making a smoothie or something else with frozen fruit. I have something called a yonanas machine that blends frozen bananas with other frozen fruits and makes something akin to a banana gelato.

If you just happen to like good food, cooking at home more often can be a godsend. Eating out is in general pretty terrible for your health. Fast food joints are pretty obviously bad for you, but most choices at normal restaurants are pretty terrible. Between all of the bread, pasta, butter, and fat going into a lot of food, one can easily consume a full day's worth of calories in a single sitting. In fact, I'm almost positive that I gained a bunch of "old" weight back because my ex-SO loved to eat out so often (especially AYCE places).

I noticed that you mentioned your SO is heavier than you. In a relationship, both participants pick up a lot of each other's habits (good and bad) and reinforce each other's behaviour. One thing I found to help for me was to try to include (not necessarily force) my SO in eating healthy and exercising. Having a partner to go on this journey with can be a great help, but requires commitment from both parties as well.