If you live in a bubble (aka Bethel), and no one ever provides you with information from a different perspective, and if anyone contradicting "the truth" is at best "disloyal" and at worst an "apostate"....
It is in fact quite easy to believe your own delusions.
And, in the case where somehow something does get through that provides evidence that it's all horse-puckey:
-- "where else would we go"
-- "if I rock the boat, I'll get expelled from Bethel and DF'ed. I'm [60+] years old with no practical work experience or skills, no savings, no retirement fund. My life quite literally depends on me never getting DF'ed. So..."