Earlier quoted context omitted.
We can only guess about what's going wrong for you specifically . But I like guessing: (extremely mild spoilers:) - A core skill for Nethack is understanding how much danger you're in at any particular moment. Your comment about soldier ants below tells me you've made good progress here. But you need to recognize when you're in danger and how long you have to deal with that problem before you'll react appropriately.…
Elbereth always seemed like a cheat... Never understood the point of it. I got to the quest without it, but not deeper.
It's been nerfed since 3.6.X as well. Now it can no longer be used for fighting, only escape, and attempting to fight while standing on it will make you "feel like a hypocrite" and deduct 5 from your alignment score.