I might well be the single least spiritual person of your acquaintance.
The vigorously philosophical atheists and agnostics who engage in discussion about their beliefs are devoting far more time than I do to matters of the spirit or lack thereof.
I don't believe in God, Zeus, Odin, Thoth, Goddess, an overriding essence within nature, an omniscient power, Buddha, Ganesh, Satan, tree spirits, New Age spirituality, Wicca, druids, pagans, "something out there," or the rest of that ilk. I don't believe in immortal souls. I don't believe in life after death, though I recognize what a lovely idea it is, particularly for someone whose life on earth pretty well sucked.
I don't crave the community and ritual associated with congregations and worship services.
I never believed in a god. Not as a child, not in adolescence, not in college, not in adulthood. I never had a flirtation with religious belief. I never tried on a denomination for size. I never grappled with doubts that my beliefs might be wrong. I never feared that I ought to choose religious faith just to be on the safe side. I didn't have my son baptized just to appease the relatives who wanted him baptized.
I do, however, have morals. I live an ethical life. I play fair. I nurture my friends and love my family. I let pedestrians in the crosswalk do their thing. I count my grocery items and never get in the express checkout lane unless I'm within two items of the allowable total. (Twelve, ten, what's the difference?) I'm a nice person.
I don't think there are many of us, in the U.S. at least, who have been this resolutely nonreligious and nonspiritual throughout their lives. How many do you know? And are they lovely people?