If it helps, I sit in the middle somewhere.
I believe you can lose your salvation not through sin but through apostasy - by willingly, actively, consciously, and knowingly rejecting Jesus as a Christian.
To do such a thing requires tremendous effort and is exceedingly difficult.
But I wonder if it's really that hard. Pride/self-righteousness is at the heart of it-an all too common human commodity.
What can I do but share my experience?
Pride comes before a fall. Don't wonder, it's impossible for the elect and all too easy for the rest. I recently messaged another member here that had thought he had done the unimaginable. Along with the following, I sent some questions to see what had preceded and how he may have recovered.
This may be a bit much for you or anyone to handle, and I know only God can really help me (if HE wills), so if you are overwhelmed or uncomfortable about replying just say so and I will desist. My name is Jason, and for about 6 months I have not been doing well. The crux of it is very similar to what you were describing about 8 years ago this way:
"A while ago I became a reborn christian. But later I came to a point in my life where I said no to God. After I said no to God all my longing for church and God disappeard. I no longer feel guilt when I sin against God, I even feel joy. And I feel love for evil things. For an example when I see the news I feel love for murderers and so on. My hart is hardened, and I feel evil, even I would never hurt anyone.
I'm sure I have blasphemed the holy spirit. WHen I think about it I don't even worry. I asked myself If I wanted to follow christ, the answer from my heart was no. But on some level I want to. I go to church almost every day."
It would be impossible to share all the things I'm being shown, but until fairly recently I'd been more or less been convinced I was saved by an experience 10 years ago that left me full of love, peace, and trust that God loved me no matter what and had forgiven me all my previous sins (and that was good, but what was bad was that it had taken any fear I had away completely, and, in retrospect, without fear what chance has anyone of being careful how they live? ). Unfortunately, this experience happened entirely outside the contexts of organized religion, and though i started to read the bible and tried attending a few church services that didn't continue long. My pride and foolishness had me believing I must have been very special for God to love me so much, and that most of the churchgoers just seemed like it was the rituals, and their choice to enact them, that saved them (rather than an act of God). And if God was with me everywhere I went then how could I ever leave Him, since He said he would never leave me. So instead of being very thankful, fearful, and understanding that it was a new life, and escape from my old ways, that I was being offered, I was almost immediately being deceived by the thought that He must finally want me to be happy in this life. Long story short, this did not end well; and I've finally come to a place where you may have only thought you were, but I am almost certainly at. And it's only now that I can see I have been hardened and evil, and am disgusted at all the wickedness I have done, and all after the fact. Now, though I have stopped any and all known sin, it seems like it's too little too late. Now I can't be sure if I am able to truly repent, or if my tearful prayers are only out of fear rather than contrition. The parable of the unclean spirit being removed from a man then returning with 7 more more wicked than itself was one I didn't understand at the time of my "second birth" but which has become all too clear now. But there is the likely possibility that you only thought you were being unfaithful, but it was something that brought you back into right relation to your Creator. But I am being shown I have definitely been unfaithful and from the point of Heb 6:4(having been given the taste of heaven) to Heb 10:26 and 12:16-17(having abused grace, but without realizing it or intending to). Now the best case scenario is that I'm being chastised, and the worst case scenario is I'm beyond the point of no return.