So tormented was Mr. Bowe by his inability to make the relationship work that he set out on a two-year quest to find out why. Not through conventional means, like psychotherapy, but by researching other people’s romantic experiences.

The result is “Us: Americans Talk About Love,” a new collection of first-person accounts of why love succeeds or fails, published by Faber & Faber. No aspect of lust, greed, need or devotion is ignored: The book includes tales of obsession and confusion (from a 17-year-old girl in San Antonio, Tex., who can’t get over an ex-boyfriend and a drug-addled 30-year-old living with his mother in Arizona while following his ex on Facebook); finding bliss (as a 44-year-old lesbian eventually did in Minneapolis, after more than a decade of marriage to a born-again Christian); and acceptance (from a 76-year-old widower in Manhattan who says he dated more than 300 women after his wife died, without ever finding anyone to take her place).

It is as compelling as literary fiction, and the Los Angeles Times Magazine called it a “profound, touching work.” But it also functions as a kind of self-help manual, forcing readers to examine their own longings, failings and assumptions about love.