I had sort of the same problem when I was working in the office full-time when I'd always worked from home. It was really tempting to get take-out or eat processed things that could just be heated up, because I was so tired from the commute.

I didn't really resolve it. Fortunately, I am working from home again and have more time to prepare meals. I can even get started on things during the day.

I like Divine1966's idea of prepping healthier foods in advance and freezing them to eat during the week. Maybe you can set aside some time on the weekend to shop and cook.