"You know; if someone without an eating disorder doesn't eat enough on Monday, on Tuesday he or she will probably eat more to make up for it, because the body didn't have enough energy the day before, right? Now imagine that on a much larger scale. For months, or even years, you've restricted, over exercised or purged.
When you're eating again your body realises that it works better when it has energy, so you get hungry. Really, really hungry. Waking up twice every night to eat-hungry. Three breakfasts, two lunches and two dinners-hungry. Ravenous ten minutes after a meal-hungry. You think 'This is my worst nightmare! Why is this happening to me?'.
Well, this is why: your body has a calorie deficit. You have thousands and thousands of calories to make up for. It all adds up and now it's caught onto your recovery and the organic structure of yours wants it in. 'Let me heal. I'm hungry!' Your body will try to get all those calories and nutrients it's missed out on as fast as it possibly can; thus squeezing months worth of hunger into a couple of weeks.
So, you're not greedy, neither are you binging; you're hungry and that's okey."