People do not usually stick with non-rewarding behaviors.
So, even though you may think you want to lose weight more than anything (but you keep failing to do it), maybe the rewards you are getting that are connected with overeating and being overweight are too hard to give up.
If this sounds ridiculous to you, it may not be.
Try to acknowledge what overeating or being overweight does for you - the "pro's" (not the cons) of both. Then you have a chance to figure out other, better ways to get those "pro's".