Adele calls Glennon Doyle “an absolute don”. Oprah raves: “It’s as if she reached into her own heart, captured the raw emotions there and translated them into words that anyone who’s ever known pain or shame – in other words, every human on the planet – can relate to.” Reese Witherspoon preaches: “This book spoke to me so loudly and clearly… I swear I highlighted something in every chapter.” And Doyle can now add this former self-help cynic to her devotees, although I’m not sure I’ll make the book cover.

I started reading Untamed by US author Glennon Doyle recently, specifically to write a feature unravelling why it sold more than 1 million copies in just 20 weeks, why its author has 1.9 million followers on Instagram and how she’s raised more than $25 million for women, families and children in crisis through her charity Together Rising. I was tasked with understanding how one woman has people across the globe following every word on her blog Momastery, why her 2013 TEDx talk Lessons From The Mental Hospital has been viewed more than 3 million times and whether she might just have the secret to genuine happiness.

Seven days later, as I pinball from one profound realisation to another about how I live, how I parent and why I fear the things I do, my husband laughs: “God, that bloody book again?” And it is that bloody book. But before I tell you why that book and its message is so powerful, here’s some background: Glennon Doyle was born in Burke, Virginia, in 1976 to loving parents, yet became bulimic at just 10 years old. By 13 she’d had her first alcoholic blackout. At 25 she fell accidentally pregnant, at which point she decided to get sober, get married and get happy – and ended up writing her blog, then a book (Carry On Warrior) about it. Her USP was truth. Pure, unflinching truth about her “rock bottom” – and how she dug herself out of it. That book sold and sold and women everywhere began to tell her about their rock bottoms, their failures and their secrets too.