I find that I have to make my comparisons properly in order to keep things in perspective.
I sometimes find it really hard to make "healthy made at home food", and so end up eating out (and really not healthily at all). Likewise, I sometimes think prepared foods are "so expensive" but again, I'm comparing them to making things from scratch, rather than eating out. I know that prepared food has more of all sorts of additives and sodium than home-cooked stuff. I just have to be realistic about what I'm willing and able to do. Given that, I've acknowledged that purchasing prepared food is often a better choice than eating out--both financially and in terms of health.
So, I eat a lot of frozen meals for lunch. I'm starting to bring fruit or a small salad to go with them, since 280-330 calories isn't enough for a meal.
I buy some salad fixings already prepared, especially shredded carrots, and sometimes bagged lettuce.
I do several days worth of chopping at one time. (A friend calls that 'butchering salad'.) It's a lot easier to put together things to take with me if I'm assembling and not cooking. I don't like to premake entire salads because the veggies don't all last the same amount of time. (Hint: put a piece of paper towel in the ziplock bag with your veggies--it absorbs moisture and the lettuce and such don't wilt as quickly.)
If I am cooking at home, I prepare the next day's lunch while preparing or cleaning up dinner, which saves a lot of time. So, when I measure out the fruit for dinner, I put an additional helping in a container for lunch. When I make up the salad bowls for dinner, I make an additional lunch sized one at the same time (and add in meat and cheese).
I don't really care for the texture of canned chicken, so I've started cooking extra chicken breasts and putting them in the freezer. I can pull one out at dinner time and it's ready to cut in the morning to put on my (already made) salad for lunch.
They're all little things--but they add up.
Goal: Back to where I was!