She may have looked pale and weary but at least she didn't have to be carried out of the nightclub.

The last time Britney Spears had a night out with her friends she collapsed on the dance floor.

But after a brief recuperative spell in a spa, the singer obviously felt ready for another night on the town.

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Her black outfit accentuated the pallor in her skin and exhaustion in her eyes as she and one of her dancers called it a night.

Three days earlier she is said to have collapsed while drinking champagne at a New Year's Eve party.

According to U.S. reports, Miss Spears, 25, checked into the Sanctuary spa in Arizona the following day to recover.

Her parents are said to be urging her to seek therapy after a dizzying month of drinking and socialising.

"It's just been heartbreaking for her parents to watch Britney on this downward spiral," a friend said. "It's so sad."

Her stay at the spa must have done some good. On Wednesday evening she felt strong enough to go out clubbing again in Hollywood. Fears have been growing for Miss Spears since she announced her split with husband Kevin Federline, the father of her two children, in November.

The singer who became world famous at 17 with Hit Me Baby One More Time, marked the occasion by hitting the town with Paris Hilton.

She was pictured falling out of nightclubs in low-cut tops and, as she grew more outrageous, even no underwear.

Yesterday Miss Spears apologised to fans after her biggest unofficial fan website, World of Britney, announced it was closing down.

"I do understand all the reasons that went behind making that decision, and I am sad to see it closing. But trust me, I get it," she wrote on her own website.

"I know I've been far from perfect. But I want you all to know that I love my fans so much.

"I look forward to coming back this year bigger and better than ever."