It sounds as though whatever mental process you went through, you managed to embrace both your insignificance and your mortality. That’s a good thing, in spite of the circumstances.
You let go, and in letting go, you stumbled into some enlightenment. It should be said, though — the peace you’re experiencing is a manifestation of life, not death. You’ve been given a gift. Spend some time with this new mental state. Explore it. Learn from it. Don’t waste it by actually killing yourself.
You can let go without giving up.
That is just about the best, warmest and most compassionate advice I have ever read.