Trying to "diet" temporarily and then pig out on shit food, will never get you anywhere.
The only way to make meaningful change is LIFESTYLE CHANGE. Eating a healthy diet, getting good sleep, minimizing stress, etc.
It all depends on how bad you want it. If you don't mind the emotional highs and lows of eating shit food and abusing your body, you're welcome to stay on that train till the last stop, it's your life, you can do whatever you want with it. For most people, change is the hardest thing.