Brave Cheryl Cole hid her heartache to wow a star-studded audience at last night’s Brit Awards. The supercool singer gave a gutsy performance in the wake of the latest revelations over her footballer husband Ashley’s alleged cheating.

Just hours before going on stage, onlookers said Geordie Cheryl, 26, appeared “red-eyed and close to tears” and just wanted to be left alone. But she emerged triumphant after vowing: “Nothing’s going to ruin My big night.” After she strutted sexily around the stage belting out her track Fight For This Love, one onlooker said: “She’s absolutely amazing. “You’ve got to hand it to her. She’s tough, cool – and tonight she’s just blown everyone away.”

Earlier yesterday there had been a rumour that Cheryl was set to pull out of the show altogether.It came after England star Ashley was accused of twice sneaking a blonde secretary into Chelsea’s team hotel for trysts in his room.

FIGHTER The pair had allegedly text messaged each other for weeks before arranging to meet up for sex before a match against Hull on October 29, 2008 and then two weeks later on November 14, when the team was playing West Bromwich Albion.

Cheryl was previously left reeling after naked pictures of the England star were allegedly sent to glamour model Sonia Wild. But sources close to the singer last night insisted that she “never, ever” considered scrapping her performance in light of the claims.

One insider said: “She won’t let anything get in the way of her big night. She is focused and just wants to enjoy the moment. “Yes, the timing is not good but first and foremost, she is a performer and she would never let anyone down. She has worked extremely hard to get to where she is and she deserves every success. She’s nothing if not a fighter.” During afternoon rehearsals at Earls Court yesterday, onlookers said the the 26-year-old looked withdrawn and stressed.

Arriving at 1.15pm with an assistant, she shunned the backstage hospitality and headed straight to her dressing room which was decked out with white lilies. One onlooker said: “As she arrived, she slipped off her black sunglasses as a man with a clipboard guided her to her dressing room.

“She appeared tired and her eyes were red and puffy. Normally she oozes confidence, but she seemed meek and very quiet.” Cheryl cancelled all interviews backstage – including a planned photoshoot with upmarket Vogue magazine – and shunned the red carpet as she locked herself away in her dressing room.A source said: “It was made very clear by Brits organisers that any personnel backstage were not allowed to speak to her.

“There was a clear directive that Cheryl should be left alone.” The source added: “While all the other acts chatted and relaxed Cheryl was nowhere to be seen. “She just hid herself away. And when she did finally emerge for rehearsals, organisers booted all the photographers out of the auditorium.

“She wanted to remain focused and concentrate on the performance. She hates all the circus and wanted nothing to detract from her day. “The organisers were happy to go along with her request.” Another insider said Cheryl had seemed on edge and slightly distracted. He added: “She didn’t seem herself.

“She kept gazing nervously at the flanks of the stage and the smattering of people dotted around the venue.NERVOUS “But when it came to her big moment everything changed. She suddenly snapped back into the brilliant performer she is.“It was as if she had managed to put everything out of her mind apart from putting on a sensational show. And she did just that.” The singer’s bandmates, Nicola Roberts and Kimberley Walsh, had sent her messages of support.

In one rare backstage snap posted on Twitter, nervous Cheryl was pictured from the waist down, pacing her dressing room in a pair of peep-toed Louboutin high-heeled shoes. Friends say she was determined to put “her all” into the performance despite initial misgivings about whether she should do the show.

Her management had been convinced she’d be nominated for Best Female having been one of the top-selling girl artists of last year. Instead she was nominated in the fan-voted Best Single category – and given one of the top slots in the glittering two-hour extravaganza.