Committed, By Elizabeth Gilbert

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How do you solve a problem like selling seven million books? Elizabeth Gilbert's Eat, Pray, Love was the story of one thirtysomething's bitter divorce. Gilbert spent a year rebuilding herself after her marital fall-out and this construction project became a monster hit. Championed by Oprah Winfrey, bought by millions, being turned into a movie, Eat, Pray, Love was a highly personal account of a year of soul-searching that went public in a spectacular way. Gilbert's follow-up, Committed, starts with an aside about the difficulty of writing anything when you know that so many people are waiting to read your work. So tricky does she find it that she pulped the first draft.

Sub-titled "a sceptic makes peace with marriage", Committed starts with the author happily involved with Filipe, the Brazilian man she met during the "Love" stint in Eat, Pray, Love. Both are divorced; one of the cornerstones of their relationship is that they will never marry. But if you want to make God (or in this case, a representative of the department of Homeland Security) laugh, tell him your plans.

As Filipe arrives in the US after one of the peripatetic couple's jaunts overseas, he is informed that he can't return. He and Gilbert must marry in order for him to secure a Green Card. Filipe is deported and Gilbert left to plan their state-enforced shotgun wedding. Committed is her way of coming to terms with the institution she swore she would never enter into again.

Part memoir, part historical and sociological study, Committed shows what Gilbert does best. Going into the intimate details of a difficult time, she is happy to share herself with her readers in the way that made Eat, Pray, Love such a runaway success. But, at least to begin with, her marriage (well, anti-marriage) obsession can be frustratingly self-absorbed. As she picks apart her feelings yet again, the urge to hiss "it's just for a Green Card! Get over yourself!" is ever-present.

However, when it comes to weaving together her broader thesis on marriage, Gilbert's skill is undeniable. She has a knack for discovering dynamite facts; for explaining complex issues in an engaging way. She cuts through statistics and offers concise findings studded with fascinating stories, from family, friends, and the odd Vietnamese wise woman, to support - or undercut - her reasoning. Her magpie mind leads her from topic to topic, while her quest to be reunited with Filipe brings the book together, legal letter by legal letter, sleepless night by despairing day.

The more one reads, the more understandable Gilbert's repudiation of holy matrimony (which, as Gilbert relates, wasn't holy at all for many centuries) becomes. Even now, married women live shorter lives and have less money than their single peers. For centuries, they could own no property and were effectively silenced as soon as they became the property of their "better" half. Married women are more likely to die a violent death (at the hands of their partners) than single ones. Gilbert's 21st-century objections to getting spliced are much less irritating when one understands how bleak marriage was for so many women for so many centuries – and still is.

Sometimes the endless working-through of Gilbert's big issue feels self-indulgent, but every time she starts fretting about how she doesn't want a party, doesn't want bridesmaids, doesn't want to be a wife, she lands a sucker punch with some razor-sharp piece of self-analysis or a thought-provoking exchange. These broaden the book's scope beyond one divorcée's therapy session and into a must-read for anyone who has ever thought about getting married or wondered what marriage means in the 21st century. Problem solved.