Amanda's unsisterly glee makes for very unpleasant viewing
Proof, if proof were needed, that no one gets the boot - or should that be pointy-toed stiletto - into women better than other women. Just look at how Amanda Holden relished a public sniggerfest at the horrific sex tape misfortune that has befallen Tulisa.
On the Alan Carr: Chatty Man TV show, Holden gleefully owned up to watching the X-rated video: "It's a terrible thing to confess but everyone wants to see it. It was her."
Then, just so Tulisa knew that all the other girls in Holden's gang were also laughing at her behind her back, she added for good measure: "Alesha sent me the link."
Cheers, Amanda! Good on you, Alesha! There's sisterly solidarity for you! Thanks for reminding all those pervs that Tulisa's humiliation is still out there in cyberspace!
There's something deeply unpleasant, crass and nasty about Holden's mirth. Yes, I know there's also something deeply unpleasant, crass and nasty about Tulisa's sex tape.
But the X Factor judge has been stupid and naive in the extreme while Amanda's shrewdly picking off her target.
And Tulisa has paid for her mistake with a public mortification that would have broken the spirit of many. To her credit, she's soldiered on through the crisis.
Don't be fooled by those photos of her out and about, all smiles and business as usual. The 23-year-old has been engulfed by a nightmare, brought low by some lousy bloke who wanted to make a fast buck on her celebrity or get back at her for leaving him or something like that. Now, just when the fuss is ebbing away, the last thing she needed was a publicity junkie like Holden scoring cheap points at her expense.
What makes it worse is that Holden is not some wannabe airhead who doesn't know any better, but a 41-year-old mum-of-two and veteran showbiz pro laughing at the misfortune of a woman almost half her age.
Who knows what motivated her to dump on Tulisa? Maybe she feels threatened by a younger woman in the Cowell camp? Maybe Britain's Got Talent needs all the publicity it can get? Maybe she thought it the height of wit?
Simon Cowell's recently been depicted as a kind of Carry On lothario, having an affair with Dannii and lusting after Cheryl.
But ironically - and to his credit - unlike the coven at BGT, he gallantly sprang to Tulisa's defence, saying she'd keep her X Factor role.
This wasn't a decision made for the sake of the show. It's already struggling and Tulisa hasn't yet inspired the sort of audience rapport that would have petitions clamouring for her reinstatement. If Cowell had dumped her, he'd have taken no hurt. Clearly he felt both sympathy and loyalty.
Still, Holden's performance isn't remotely surprising. We all know that women are routinely vicious about other women - bitching about their hair, what they're wearing, their cooking - while men rarely bother on these fronts.
Perhaps it's partly because guys rarely notice such trivia, but it's also because they're not insanely jealous, riddled with insecurity and threatened by other women.
From school to the workplace, sniping is the default position of women.
Men huddle in groups to discuss football or The Killing, not the state of Dave's new haircut or how Stevie's looking a bit worn.
But women gather in the loos to get their own back with barbed remarks and putdowns. They love those mags that sneer at female celebs' bodies, circling their cellulite and Botox.
Funnily enough Holden wasn't thrilled when her lips attracted adverse comment a while back, amid speculation they looked fuller than usual. If only she'd learn when to button them, we might feel a little more sympathetic towards her.
At the weekend Dr Helen Wright, headmistress of a public school in England, blamed social networking sites and celebrities for creating a generation of "mean girls".
Actually there's nothing new about bitchy women, except perhaps the level of malevolence these days. The internet is just another set of loos to stand around in slagging off the latest victim.
Shame on Amanda for egging it all on.