If your condition is as you describe than I'm sorry for you but you're one of like 0.1% of the population (probably less). It's fine, you got dealt a shit hand but you aren't saying that being obese is a healthy lifestyle and the thing is other people are.

Everyone I've ever known or read about has gained weight by eating more and lost weight by eating less, again less and more vary from individual to individual but the fact that calories in = calories out for maintenance is a law of physics.