She continues, "I put my bags and the children down, I picked up the mic and I sung. It should have been the best moment of my life, but I just wanted to be elsewhere."
The mother-of-four explains that she no longer had "passion" for the group, comprised of gal pals Melanie Brown, a.k.a. Scary Spice; Melanie Chisholm, Sporty Spice; Emma Bunton, Baby Spice; and Geri Halliwell, Ginger Spice.
"It wasn't a lack of respect for the girls or the audience," she notes, "but the passion just wasn't there. By contrast, in my new career, the passion grows every year. I still want more."
The 39-year-old also explains that her pouty, sourpuss persona was a way of coping with her Spice Girls fame.
"I looked moody. But I wasn't! I was shy, not very sure of myself," she's quoted as saying. "The other girls would sing and dance on tables with no complexes, I wasn't confident enough to do that."
She adds, "I had to invent a character and I thought of that: staring at people and pouting.
"My insecurities helped me create the character in a way. Nowadays, it's like a barrier that comes back whenever I go out in public. That's the way fame has affected me."
Lady Beckham also touched on her move to Los Angeles with husband David when he signed with the Los Angeles Galaxy of Major League Soccer in 2007.
"It could have been a lot worse: I don't have a single stint in rehab to my name," she says. "I feel more free these days. Someone said to me once, LA's like a giant rehab centre for celebs. Everyone walks around in casual clothes. It's so far away from everything that people leave you alone."
Victoria and her now retired footy star hubby have since moved back to the UK, and are rumoured to have forked out a cool £40 million for a palatial home in west London. The four-storey home is reported to have seven bedrooms, five bathrooms and two rooms for Posh's shoes.
"My life is very different than what people imagine it to be," Posh says in her confab with the magazine. "It's always me who goes to Waitrose to do the weekly shop, Harper balancing on one hip, Brooklyn hanging on the trolley.
"I go down the aisles telling the kids, 'No, you can't have that', just like any other mother. People look at me in awe like I'm from the circus, but it doesn't bother me."
The jungle drums have been beating about a possible reunion of the girl band since they performed at last year's Olympics closing ceremony.
Last December, the Mail Online boomed that the Spice Girls were tipped to reunite without Victoria, and would announce their comeback "within weeks".
A so-called "source" dished at the time: "The girls [Emma Bunton, Mel C, Geri Halliwell and Mel B] are going it alone without Victoria. They are keen to get back together and were trying to work out if they could do it as a four-piece. I think they know this is the last chance for them to get the band going again.
"But the Spice Girls as a foursome is not going to get them another record deal or sell out big venues. They need an extra cherry on the cake. And the cherry on the cake would be if they replaced Victoria."
The report claimed that the girls would hold auditions for a new member via a reality TV show "to rival X Factor", while former Sugababe Heidi Range was also suggested as a possible stand-in.
Bunton and Mel C spoke out to deny the reports at the time.
"It seems there has been some Spice related nonsense written today. None of the Spice Girls would ever or could ever be replaced #justsayin x," wrote Mel C.
Echoed Bunton: "None of the Spice Girls would ever or could ever be replaced, nonsense in the papers!!!"
Fast-forward to March, and the Sunday Mirror claimed that Posh had dropped the "bombshell" that her warbling days are over while attending a Justin Bieber concert with a pal.
Pouting and "pointing to the stage at London's O2 Arena", a defiant Posh was supposedly overheard telling a pal: "I won't sing again, I'm not getting up on stage again.
"You'll never get me up there even though the girls keep trying to get me to."
Even that declaration didn't stop the rumour mill.
2DayFM breakfast show hosts Kyle Sandilands and Jackie O then claimed a "very reliable source" had confirmed that the Spice Girls will tour Australia in 2014 - with Posh in tow.
"This is very much an exclusive announcement to make on the show, that I have just heard about. All the Spice Girls will be touring Australia," they told listeners. "No official announcement has been made, but I have a source, a very reliable source."
But a rep for Victoria put the kibosh on the reunion speculation.
"Victoria has made no secret of the fact her singing days are over, with a hugely successful business and a growing family, she loved her time as a spice girl and will always wish the other girls well in whatever they choose to do," the rep said earlier this year.
Back in April, Mel C said that a Spice Girls reunion may not be possible without Victoria.
"To have come from a pop group to be respected in the fashion world - we have so much respect for her for doing that, and she's worked bloody hard to get there. It's not a secret that her passions lie elsewhere," she told the Mail Online.
"So we can't drag her kicking and screaming, telling her, 'Come on! It's time to sing 'Wannabe'."
She added, "We did really, really enjoy doing the Olympics and would love to do something else, but would we want to do it without Victoria? I don't know.
"It's something that would need to be thought about in depth."
NOTABLE NUGGETS
And finally ...
* Johnny Depp caught with his pants down. No, really.
* He said what? Kanye West says that he's "putting [his] life at risk" when he takes to the stage during his Yeezus tour, and compares what he does to being a cop or soldier.
* Justin Bieber says negative media coverage of him feels like "bullying".
* Katy Perry has a lot more to say about her divorce from Russell Brand and her burgeoning relationship with John Mayer.
* Are they or aren't they? Harry Styles and Kendall Jenner reunite in NYC.
* Jennifer Aniston admits she had an "awkward phase" during her 30s.
* Lady Gaga dresses as a Christmas tree, baubles and all.
* Miranda Kerr breaks silence on split from Orlando Bloom.
* Did Paris Hilton order a plane to fly over Paul Walker's memorial with her name on a banner?
* Watch: Sesame Street's Lord Of The Rings parody is all about the cookies, and the "one dessert to rule them all ..."
- Rumour Has It
