I wouldn't necessarily have bet on another memoir about love and friendship. And I certainly wouldn't have bet on another memoir about artistic ambition and the writing life. But by the time I finished the first chapter of Paul Lisicky's lyrical new memoir, I was certain this was an essential book.

"The Narrow Door" recounts in an elegant and effortless voice the great romantic and platonic loves of Lisicky's life.

There's M — Lisicky's husband, a poet — who supports and encourages and adores the author, and whom the author adores in turn. It seems in many ways a perfect relationship, intimate and tender and brimming with mutual affection and admiration. The two read each other their works in progress, attend writing conferences and move around the country in support of their careers. All the while, Lisicky recounts the petty jealousies and insecurities that inevitably surface, lending the marriage a grave and foreboding authenticity.

But the even more interesting and intense relationship in Lisicky's life is the platonic one, a decades-long friendship with a woman named Denise Gess, a writer herself. It's a relationship that seems in many ways more charged — with jealousies, with longing — than the romantic one. In fact, of the many threads this book weaves, the main pattern that emerges seems to be one that properly celebrates Denise's life and the author's abiding love for her.

But don't think for one minute it's a sentimental or schlocky celebration. Lisicky explores love and friendship with what I kept thinking of as an "expert vulnerability," and the result is intimate and simultaneously heart-rending and heart-mending recapitulation of a friendship and a lifetime.

Asked to eulogize Denise (who dies after a long and courageous battle with cancer), Lisicky feels underqualified and overwhelmed, although he manages to deliver. But who could ever love someone so profoundly, in so many complicated ways, and in the hour of his truest despair put into a few words all that the person meant to them? The answer is no one. Lisicky knows this, and so writes this book in the aftermath of years, time that also sees the end of his marriage.

"How tempting it is to do the alchemical now. To turn darkness into light. … It's what narrative wants of us. … It wants to comfort, not that we should necessarily link comfort to weakness. Couldn't there be some rigor to comfort? I'd like to think the story could give it that, to give the hurting in us strength and power."

It seems essential to say that there is indeed comfort in these pages. Love explodes from them. To say it any other way would be insufficient.

Peter Geye is the author of "Safe From the Sea." His novel "Wintering" will be published in June. He lives in Minneapolis.