Stage 1: Have groceries
You have just gotten home from the grocery store and you put everything away. You feel so proud that you have done the responsible thing instead of putting it off and ordering a pizza out of laziness. You are also probably tired from this whole "modern day hunter/gatherer" ordeal, so you're not quite ready to choose a meal to cook and prepare it. In fact, there are so many god-damned options, you are having trouble even deciding what you want to eat. So you put it off. Cooking takes so much time...GOSH!
You eat a banana before bed.
Stage 2: Grocery supply begins to dwindle.
All of the really good meals have been cooked and eaten. The healthy stuff is still ok to eat, but it's now or never. The problem is that you aren't necessarily craving any of the things you still have left...DEFINITELY not the healthy stuff. And going to the grocery store is absolutely NOT an option, because there's still food in the house.
You eat the last box of Mac and Cheese.
Stage 3: Groceries are gone
There are no more complete meals left. The once-fresh veggies are shriveled and you are too ashamed to throw them away just yet. You're damn sure not going to eat them though. All you have left is half a serving of plain pasta(no sauce), a can of tuna(no bread), some tortillas(no cheese, chicken, salsa, or anything that would be put on a tortilla), and an egg of dubious age. You are completely disheartened and disenfranchised with groceries, so you're not going to the store...besides...it's 9 pm and you haven't eaten dinner yet.
You eat the plain tortillas....and furthermore for the next week or two, you order pizza, fast food, or let your 'opportunivore' instincts from your college days kick in. You will eat anything. After enough time, you somehow muster the strength and courage to visit the grocery store again.
Repeat.