One option is to cook for 4 - yourself, yourself the next day, yourself in several days, and yourself in a few weeks. Cook larger meals, planning to save off portions for later reuse. A freezer is a great benefit to cooking this way, preferably a chest freezer. A small one, for one person!
Search the web for phrases like "cook once a month" and "cook many meals at once" for ideas of meals that work well this way. One of the tricks to making it work is to prepare components of meals ahead of time, and then assemble them with a little additional cooking for each meal. For example, cook a lot of rice at one time, planning to reuse some with another meal the next day, and freeze some to add to soup next week. By cooking once a month, you can have fresh meals readily available most of the time, with less overall time invested in cooking and taking advantage of the economic benefits of purchasing larger quantities.