I frankly disagree that studying a book isn't helpful.
This is a war. In war you almost never want to oppose force with force. You want to use your enemies force and channel it in a way that leads to their defeat. That concept is a first principle of war.
By studying a book you are signaling to your wife that you are "interested" and open to her religion. You are working out your strategy but your conversion to jw is the ultimate goal of her strategies. You need to be aware of that fact and utilize it. By understanding her strategy you can harness and re-direct it.
If you aren't open to her religion (direct opposition), you are an opposer and to be avoided. In that situation you would have no chance to help her leave. You would be defeated in your ultimate goal.
Besides, I actually learn some things about the Bible from my study. Really the only problem I have with the jw, and it is very significant, is TFDS doctrine. That really is the fountainhead of all that is vile with the jw.
Were it not for that teaching they would be a nothing more than a solid group of conscientious Christians with a different take than orthodox Christianity. I might even consider joining?