Simply leave the meme your self and don't let it control you any more.
The Watchtower is a meme. Trying to kill a meme is like trying to kill a god. You can't but you can get out from under it's control your self. If enough people stop letting the meme control them the meme goes away.
Though what about those on the inside?
They are in a sence infected much like you were. They will either get better, or get worse. It's up to them.
What about the damage the meme is doing?
Memes are really good at hurting people. Though the cure is worse than the disease banning free belief is the only way to fix it. I don't think it's worth it. We may doom our selves to a worse fate a single all powerful collective that has no care for the invidual at all.