Not being able to live the lie / keep up the charade anymore.
After the 1975 debacle, I knew deep down, that the religion of the JWs was no different from any others - after all.
However - and I am not proud to have to admit this - I did go through several decades of denial after that. I tried to justify myself with the thought that if this one wasn't exactly perfect, then it was still head and shoulders above anything else. I desperately wanted to believe the Society's post-1975 propaganda that it was all the fault of "some" individual JWs reading more into it than the WTS actually said.
In the end, though, the discovery hit that you cannot hide your head in the sand forever - and all ostritches end up with are cold backsides!
Bill