I would just try making casseroles, lasagna, soup, etc. and freezing some of it for later. Like for casseroles or lasagna, you could prepare the meal in several small casserole dishes (I think the small size is about 1/3 of a normal size one) and then cover tightly with foil and freeze BEFORE baking. Then you can rotate meals over the course of 3 or 4 weeks so you won't be eating the same thing over and over. For soup, you cook the soup all the way, then freeze portions of it in 1 quart freezer baggies. You could take out the baggie in the morning or night before and by dinner time it will be defrosted enough to heat in the microwave. Also, try variations of a chicken salad, but just make half of what the recipe calls for, which will be plenty for 2 meals for yourself. I would try Kraft Foods website, they have tons of easy ideas and really inexpensive ones and they have recipes for every occasion, including cooking for 2 (which you could halve the recipe or just have leftovers).
Another idea for single serving meals would be buying frozen fish, fully-cooked frozen grilled chicken, frozen hamburger patties, etc. and then you can just take out what you need and they cook really quickly and you could just pair it with some instant rice and steamed veges or a salad or a baked potato, anything that's quick and can be single-serving.
Stir fry is always easy and cheap and if you want to use chicken in it, just buy a big package of boneless skinless chicken breasts and divide them into individual baggies with one piece in each bag. Then you can just quickly cook it with whatever marinade or sauce you want, add frozen or fresh veges, maybe add some nuts (or nuts in place of meat), and some instant rice. It's very versitile and healthy! You can also try beef stir fry or even fish (I like salmon, and they sell small salmon patties in the frozen section in a re-sealable bag so you can just pull out one).
OK one more...pasta! you can try different types of noodles, just buy a jar of sauce (which you can also buy many different kinds of), and cook just one serving of noodles and heat one serving of sauce (save the rest in the jar in the fridge), add a salad and some garlic bread on the side, and if you want to have more variety, try adding things to the sauce (chicken, ground beef, bell peppers, squash, zucchini, eggplant, carrots, etc.)
I think that's all the ideas I have for now, hope this has helped you out!