The only alternative to religious thinking is misery? That sounds very much like religion insisting upon itself, like when they claim that without the fear of god we would all be savage and immoral. It's nonsense, really.

But there were a few absurd reductions in what you said, including the idea that the prevention of suffering is tenable yet somehow nihilistic.

Would it not be more sustainable to focus on spreading joy instead of preventing suffering? That way you won't drive yourself crazy focusing on the negative aspects of humanity.