If you have MG, exercise won't be good for you right now.
If you are obsessive about exercise, that's not good either.
If you stop exercising, you'll know - after some amount of time - whether it was the "training" or a disease state.
I'm sorry you are going through all of this. You need a sensible approach and, right now, the only sensible thing is to take away the one thing that they claim is making you ill, in my opinion.
It might be the only way you can get help. And I hope you do.