I don't think I was ever aware of my heart being in that hardened state when I was still in the Church. I'm also not sure if I've ever fully identified the process of falling away. I think I just took it for granted that I did at one time leave my first love some twenty plus years ago.
Looking back, I can now see the straw that broke the camel's back. It was just one miserable disappointment after another in God for not healing me of my sins despite my desperate cries. To worsen it, all those in the congregation were acting crazy. Casting out demons, falling to the ground, speaking tongues of gibberish, praying out loud, dancing, singing, laughing, eating and drinking all for show. I took part in some of that craziness, but it felt so disingenuous and none of it was helping, so I left.
There I was one day not long after I left the Church, laying in bed without God, without a foundation, contemplating suicide. I asked God why He created me knowing full well in advance that I would not and could not repent. I asked Him why He would send me to hell for something out of my control especially if He knew I would fail. I told Him how unfair that was and if hell is where I'm meant to be because He wouldn't save me, then hell is where I want to go. I resigned myself to eternal torture, I gave up on God at that moment because in my mind, He failed me. It seemed He didn't care. I was so mad at God, I hated Him and let Him know by cursing Him. I didn't want anything more to do with God.
I don't remember much in the years between that falling away event and finding bible-truths.com, but when I did find it, my hope in God was renewed. It hasn't gotten easier, but at least now I have a foundation, and I know God is good and just, no matter what happens.