Not many years ago, I was in the same place as your parents. Though I stressed the 'truth' as the answer of course, it wasn't the answer.
My deeper concerns were for the safety and welfare of my child - if I couldn't have her in the 'truth' with us, then at least I wanted some comfort that she was making wise choices in association, not using drugs or getting drunk, and that she was not exposing herself to STD's and other life threatening situations. She ran as fast as she could into all of the above, messed up her life [from anyone's perspective not just JW], left her kids in limbo, and is spending her quality time now in Uncle Sam's free lodging and boarding house.
Has she taken a 'sane' course away from the 'truth', one that made us see that she was independent but wise in her choices, while we would have not liked that she was not 'trusting Jehovah', we would have been content to see that she was safe and happy.
I hope that you take a wise course - they will see anything you do now as rebellion against the 'truth'. Be that as it may - the best Witness against the Witnesses is a successful life. Otherwise, they could say 'I told you so' when your choices end in a trainwreck. You might be able to tell them 'I told you so' regarding the 'truth about the truth', depending on the lifestyle and respect you show here.
Good luck to you son.
Jeff