A few things I've learned along the way:
1) It is entirely possible to cook for yourself at home and make it affordable. There are a few techniques I use that make it very doable. First, I shop once a month for pantry staples such as stocks, canned goods, things in a jar that I love (like olives and pickles), and anything else heavy. If you are in a city, do this via a delivery service or by renting a car (we have car2go and Zip Car in D.C.). Before you accuse me of being extravagant with the delivery service, note that it only costs $7, while a car for an hour will likely be $10-$15.
2) Do your best to plan your meals for either half a week or a full week. Once you have your pantry stocked, it's just a matter of picking up proteins and fresh produce. I haven't had anything processed in my kitchen since starting the blog.
3) You WILL have to re-purpose food or eat leftovers. There are some things that are darn near impossible to cook for just one person. But, almost any cooked protein can be tweaked into an entirely different meal.
4) Don't expect to achieve greatness every single night. If you notice, I have some less than gourmet food on the blog. Then again, I have some things that I think are masterpieces! My whole idea is to eat something different every day, making food exciting and engaging... not just something you're mindlessly shoveling down your throat.