That sounds to me like some kind of severe depression or similar. Trust me from experience — it is NOTHING to do with God; it is NOTHING to do with your state of salvation. It's just error, or evil, or the tempter, talking — and all he can ever do is lie, as Jesus himself said. God has not left you; how can He, when He's already everywhere? ("Do not I fill heaven and earth?" says the Lord — Jer. 23:24)
It hurts my heart when I see young (and sometimes not-so-young) people on this forum who've been terrified into a state of near paralysis by these fearmongering theologies that bang on about apostasy and losing God's grace and being lost forever just because you've slipped into doubt or despair. Most of Christianity doesn't teach anything like that, only the fundamentalist fringe. If you're going to a church like that, get the hell out of it and find somewhere that actually helps you to feel the saving, healing love of God. Find someone you trust as a counsellor, if you need to speak to someone one-to-one and confidentially. Pray that God will guide you to where you can hear and feel Him again and know that He never left you after all — because that IS the truth, no matter what your feelings (or lack of feelings) tell you. And He can always hear you, even if you feel like you can't hear Him. As Lismore says, the fact that you care at all about this is more than proof that you aren't a lost soul. Keep going, just keep going. You are dearly, dearly loved by God and you WILL discover that again.
