Hey max, how are you? I'm sorry that your weight and eating problmes are keeping you from having a normal life, but I can definitely relate so you are by no means alone. My eating problems also has me thinking about food a lot so I know how it is to fight that thought all the time. Somtimes your own body feels like a prison.
I guess you should ask yourself why you gained all the weight back? Were you eating more? Were you using food as a comfort source? Were there complications from surgery? Also did you have an eating disorder such as complusive eating before the surgery? This might have followed you after your surgery as well. This is what it sounds like to me.
Eating disorders are frustrating and tiring, they can really drain you emotionally and physically. But there is help for those who choose to take it. Reach out to someone and they will reach back. I can't advice you to go to a Dr. Immediately because I would be being a hypocrite. But I hope that you don;t end up like me- keeping it a secret which begins to control you I hope you go to therapy like lostoyou mentioned. Think about it, its your life, you have control over it. Keep me posted and remember you are not alone and there is a solution if you look. :d