I think you answered your own question. The less you say, the better. If you are still dependent on your parents for a living, things can get rather touchy.
You can use depression or just say you lack motivation to go to meeting/field service. That would be true enough.
I don't know your situation, but if your young, you need a plan. You need to build up a network of friends outside the jws. Maybe you can go away to college?