It was a number of things that set me off. Like Scully, I was treated in a very shitty way by the congregations I was in, to the point where, while I was still a believer, I had no desire to survive armageddon™ and live in a world filled with such assholes. I had decided that, should I survive, I would shoot myself. I was enraged when I became aware of the scope of the child abuse problem and the Society's policies on it. That led me to do a thorough investigation of the doctrines and history of the organization.
In retrospect, I'm very happy that Jehovah's Witnesses treated me like shit, and that I had no friends to leave behind. It made it easier to do an honest investigation into my beliefs and the organization I was associated with, and it made it much easier to leave.
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