If you knew that changing a habit is a process of skill development and not a test of your willpower, would this make a difference in your weight loss efforts? A learnable skill that is key to habit change is breaking down habit change into smaller, more manageable tasks that you can address one at a time.
If, for example, your weight-gaining and weight-maintaining pattern of eating is to indulge in fattening snack food in between meals, how would you go about breaking down this habit into smaller, more manageable tasks?
You could, as a first step, select the between meal snack that is easiest for you to concentrate on and possibly do something about. Next, without trying to change your snacking behavior, you might see what your triggers are for snacking at that time. Then, you could try to eliminate, change, or substitute something for just one of those triggers.
Get the idea? Changing your weight-gaining and weight-maintaining eating habits is what you make of it. It will work best for you if you make it a process of skill development rather than a test of willpower.