I grew up very religious and when I lost my faith in my 20s, I tried to replace it w/ absurdism and existentialism, but couldn't shake the notion that lives deep in me that ultimately, even if humanity spreads across the cosmos and we're able to find meaning in our own individual existences, the universe will inevitably suffer heat death, from which there is no eternalistic escape.
These days, my morality entirely stems from the reduction and prevention of suffering, which is ultimately the only moral currency we have.
This led me to veganism and anti-natalism, as the best way to prevent individual suffering is for the individual to never exist in the first place (see: David Benatar's Better Never to Have Been; or Ecclesiastes 4:2-3). Needless to say, these are wildly unpopular philosophies. In light of this, I began to come to the realization that we're all nihilists at our core. We embrace religion or other philosophies to ward it off, because it's a truly uncomfortable sate of mind, as the author notes in this post, and the only alternative is total misery until we die. And then, depending on your philosophy, perhaps a true eternal bliss awaits you in paradise! How convenient! The happy people among us are the best at this practice - lying to ourselves successfully about the true nature of reality. We don't care what gets us there, as long as we get there.
All this to say: I was much happier when I believed in God.