How the X Factor judge and Girls Aloud singer captured the nation’s hearts.

I have a serious girl crush on Cheryl Cole. Not in a Katy Perry, faux lesbian, I-kissed-a-girl-and-I-liked-it kind of way. This feels like I’ve regressed to being 13 years old and wishing the coolest girl in school would be my best friend, share her trendy clothes, gossip about boys and spend hours poring over Dirty Dancing in a bid to learn the hip-swivelling moves. A straw poll of female friends concludes I’m not alone.

And the guys? Rather than reverting to the salivating brand of smut you would expect of a red-blooded male talking about a bona fide pin-up, they go all gooey-eyed and mushy, talking about what a “lovely girl” she is. Mums and dads love her, young girls worship her and grandparents want to pinch her cheek (who can resist those dimples?). Cole has even melted the heart of Simon Cowell, a man who was previously considered to have a fistful of dollars stuffed in the black hole where his compassion glands should reside.

It’s difficult to remember a time when Cole wasn’t the darling of the nation, yet it’s only a little over 18 months since she made the kind of dramatic, 180-degree transformation that not even an army of stylists and svengalis could have pulled off. Almost overnight Cole evolved from one-fifth of Girls Aloud and tacky footballing Wag to become the most compelling reason to watch Saturday night television, not to mention respected fashionista, glowing role model and a contender for Britain’s modern-day Eva Peron.

In FHM’s 2009 poll, the 26-year-old Geordie was voted “sexiest woman in the world”; her Vogue cover, in February, was a bestselling issue; and last December Liverpudlian painter Lee Jones unveiled a pop art portrait depicting Cole as the Angel of the North. “I see her as a new icon of popular culture for the 21st century, a beacon of light in these bleak times,” he said. Most recently she has become the face of hair care brand L’Oreal (because she’s worth it).

So what is it about Cole we love so much? It’s not really about the music. And while the fact she is super-pretty with a figure to die for doesn’t hurt, it’s her unique brand of down-to-earth, no-nonsense, wears-her-heart-on-her-sleeve frankness we have fallen for. Cole is open, direct and kind. She has no qualms about standing up for herself (not least to the often belittling Cowell) or showing her emotions. She will be the first to comfort upset auditionees and openly cries when upset. She exudes a vulnerability it is impossible not to like.

Perhaps most intriguing is the shift in the cultural landscape which has seen Cole become an icon. She is the anti-thesis to a decade of brash and vulgar female celebrities, a breed pioneered by the likes of Katie Price, who, in her alter ego as glamour model Jordan, inspired a generation of young women to take their clothes off and earn a fast buck. Cole, in contrast, is the poster girl for traditional values. She has a strong moral compass and espouses the joys of the family unit, describing her “mam” as her best friend.

While in the eighties it was the raw, edgy sex appeal of Madonna which captured the mood and the nineties brought the pseudo-feminism of The Spice Girls, Cole, perhaps more by accident than design, has tapped straight into the noughties zeitgeist. Now it’s not about sex, money or taking over the world, rather we are craving something more real and tangible – and amid the fakery of so called reality television, Cole represents ingenuousness and hope.

When Cole steps out from behind the judging desk and up to the mic on tomorrow evening’s show, it will mark a watershed moment for the singer. She will be emerging from the shadow of one of Britain’s most successful girl bands to fly solo. On paper you would expect Whitney Houston, also performing on The X Factor this weekend, to be the star attraction, given the gory back story, but it is Cole that the nation is clamouring to see.

So where did it all go right? Things haven’t always been so shiny happy for her. The singer, then Cheryl Tweedy, grew up on a tough council estate in Newcastle. Her ambition shone from an early age, as she appeared in modelling competitions and became the child star of TV adverts, including two for British Gas. Aged nine she won a scholarship, sponsored by the Daily Star, to go to summer school at the Royal Ballet in London.

It’s unsurprising that, having so fervently chased the dream of fame, when Cole found it on reality show Popstars: The Rivals in 2002 she held on for dear life. Back then, Girls Aloud were the pretenders to the Spice Girls’ throne, a band adored by teenyboppers but one which no self-respecting adult would admit to liking. In those early days, Cole gained infamy after getting into a fight with a black law student toilet attendant in a nightclub in 2003. She allegedly made racist remarks and was tried, found guilty of actual bodily harm and sentenced to 120 hours’ community service and a £500 fine, but the jury ruled that the assault had not been racially motivated.

Her notoriety went up a notch after marrying footballer Ashley Cole in 2006, the pair signing an exclusive OK! magazine deal reportedly worth £1m for their wedding snaps. A cringeworthy promotional shoot for the National Lottery that same year – the couple wearing matching tacky white outfits and posing in front of a posh car – saw them dubbed “a poor man’s Beckhams”. It was this crass behaviour which apparently prompted Lily Allen to pen her acerbic B-side track, Cheryl Tweedy, in which she snidely remarks: “I wish my life was a little less seedy/Why am I always so greedy?/Wish I looked just like Cheryl Tweedy.”

Cole, it seemed, was destined to be scorned. Then, in January 2008, came the most unexpected sea change when a tabloid ran a story about hairdresser Aimee Walton, alleging she had spent the night with Cole’s husband Ashley. Then another girl surfaced, Scottish model Brooke Healy. Suddenly Cole was seen as a victim, the wronged wife. The nation’s heart went out to her. “Leave him,” we cried.

She didn’t, but throughout Ashleygate, Cole conducted herself with silent dignity. Off came her wedding band, but there was no Katie Price warts-and-all revelations. Nor did she storm the divorce courts to take her multi-millionaire spouse – dubbed “Cashley Cole” for his outlandish salary demands – to the cleaners. That’s not to say she let him off lightly. If reports are to be believed it took him months to get back into her good books. Even now, Cole appears reticent about getting hurt again, saying recently she only trusts her mum and her dogs.

Ironically, while her personal life was in freefall, her professional life skyrocketed. When Sharon Osbourne quit The X Factor in June 2008, it was Cole who was ushered in and brought a lot to the table. Cole had compassion, empathy and a feisty, inextinguishable spirit. It was spellbinding to watch. The nation rallied. Those who had knocked her were suddenly behind her. To cap it all off, Alexandra Burke, one of the young women mentored by Cole, was crowned winner.

This Sunday will be D-Day as Cole performs her debut solo single, Fight For This Love, for the first time. The critics are already poised like tightly coiled snakes, not least with the news this week that she will not technically be performing live but will pre-record the song in front of a studio audience.

It smacks of double standards. Each week X Factor hopefuls spend hours rehearsing in preparation for singing live before 14 million people, yet one of their judges – and mentors – will, if reports are to be believed, mime large sections of her own performance. Cole’s nerves must surely be jangling at the thought of the show that made her breaking her. Lesser mortals would fall on their swords. However, one can’t help but feel that the public will only love Cole more for laying bare her flaws.

Fight For This Love is on sale now. Cheryl Cole’s debut solo album, 3 Words, is released on October 26.