My OH works away quite a lot and so I often find myself in your position. I tend to half the recipes and then I have a portion for my dinner that night and a portion for my lunch the next day.
Or think of recipes than can be adapted. For example you can make a bolognese for one evening and then the next day add some more stock, chilli and kidney beans and you have got yourself some chilli for the next meal!! Or bolognese can easily be made into cottage pie for the next day.
Or if I am alone for 3 or 4 days I will buy a whole chicken and roast it. On day 1 I will have a roast, day 2 I will have pasta bake with chicken in, day 3 I will have chicken stir fry and if you have any left you can have toasted chicken and cheese sandwiches the next day.
Even when he is at home gracing me with his presence I make enough for 4 and freeze the remaining portions. There is then enough in the freezer for if he is away and I cannot be bothered to do more than heat something through or if there is some sort of national disaster I am not going hungry for quite some time!!!
I hope that helps!