Yes, I agree with what was said here. Just because you've tryed a lot of ways and they didn't work, it doesn'te have to mean that you don't have any more chances.
Look, don't give up, but don't forget that losing weight in your case can be good but only if it's done in an appropriate way, because being healthy is, I keep saying this, the most important thing.
If you want to lose weight by starving, for example, you may lose weight, but that will be bad for you, because you'll be playing with your organism instead of listening to it and dealing with it in a good way.