You are not "plus size" you are morbidly obese - it's your choice. That being said, you made that choice, not the airline. Pay extra for extra space or shut up about it.
Well, guess what?? You're a man, still, always and forever, and you are expected to use the men's room and not project your fantasy to others who do not want to be part of it.
It's time for you to stand up to your responsibilities and quit blaming everyone and everything for your failures - if you want something, work for it. Act decent. Stop yelling victim when you are the problem.