Cooking and shopping for one

Cooking and shopping for one is really difficult. I end up using the same ingredient for about 3 days in my dinners bc otherwise it goes bad and is wasted. That ends up being 6 meals bc there are always left overs. Not sure how to deal with this. I don't want it to get to be annoying to the point that I get to snacking bc I'm bored. I have learned not to buy the junk bc I will eat it. Ie cookies. Ugh. But it is also making me get creative on recipes.