When I remember the summer of 2012, I'll think of rain, the Olympics – and an epidemic of stage-managed sapphism like no other in living memory. When Gillian Anderson called recently for "a more nuanced conversation about sexuality and its fluidity", I had to snigger as I recalled how Oscar Wilde's boyf once famously described the desire for one's own gender as The Love That Dare Not Speak Its Name. Well, times have changed, and homosexuality – at least for showbiz starlets – is these days the love that can't stop nudging, winking, smirking, insinuating and straight-up showing off about itself.

An actress might dress it up in fancy language, but our singing sisters are predictably far more basic about bisexuality. The pop starlet of the moment, Rita Ora, and yesterday's indie pin-up, Avril Lavigne, were both pictured posing saucily with female friends on holiday this summer. Last year, Cheryl Cole revealed that she had a "girl crush" on Rihanna before she presented the bodacious Bajan with the Brit award for best international female. To be fair to Chez, you can't say that Rihanna wasn't asking for it; previously RiRi had opined: "She is the most beautiful woman I have ever seen. How do you have a face like that, with hair like that and dimples, and a body like that, that's proportioned like that?" A quick grapple as the prize changed hands and Rihanna obligingly tweeted: "Can Cheryl Cole NOT be so yummy??? Just ONCE!!!"

Then this summer in Esquire magazine, Rihanna upped the ante – or something – when she expressed a desire to see the Geordie sexpot getting down and dirty in the course of cleaning up: "I would just like to watch her work. Preferably cleaning things on the floor. Picking up stuff on the floor. Bending over... she's hot! She's so beautiful." Would Cheryl be suitably attired or, indeed, wearing clothing of any kind? "Oh, as if!" And then to show that she was a keen appreciator of female beauty, Rihanna threw in, when Adele's name came up: "I want her. Adele, come on!"

Perhaps piqued at this curvaceous competition, Cheryl was all over Rihanna's BFF Katy Perry – the woman whose song I Kissed a Girl sparked a thousand drunken thespian-lesbian displays – on The Graham Norton Show a few days later. But just so we are sure of who her heart really belongs to, KP said in a recent radio interview that she didn't know whether she and Ri would ever collaborate musically – "but we're going to have sex".

Girls, girls – get a room. But would it be a bedroom or a boardroom? That's the question. How much of this yearning is physical – and how much is fiscal? Ever since the queen of the beat music bi-tries, Madonna, snogged Britney and Christina on the same stage, no pop tart ever went broke by underestimating the liking of your average fanboy for a bit of girl-on-girl body surfing.

How times have changed! When I left my husband for a girl 17 years ago, the rotter divorced me for "unreasonable behaviour". As I pointed out at the time to my lawyer – the girl in question being a ravishing 25-year-old heiress – "Look at her! It would have been unreasonable not to do it." Once, calling a woman a lesbo was the most embarrassing, shameful thing you could say to her. But these days, you can easily imagine a man divorcing his wife for the unreasonable behaviour of not making out with another woman and letting him watch. And pop starlets are suss enough to know this. There's the rub, so to speak. If Chez, Ri and KP are doing this to titillate their male fans, there's something somewhat sad and shabby about it.

Rihanna is believable as a bisexual; she's just so seriously hedonistic, and surveys have shown repeatedly that the more women like sex, the more likely they are to enjoy it with both genders. Her alleged affair with the model Natasha Burton was written about in the temptingly titled book Low Down Dirty Shame: "Sex came up immediately – she was a freak... I was on my spiritual journey and sex wasn't a part of my plans. However that didn't stop her..." Rihanna's erstwhile lover and attacker, Chris Brown, with typical discretion and perception, reacted thus: "She is not a lesbian. I should know. And if she was a lesbian, then I would have had a threesome, but I didn't have a threesome, so she can't be a lesbian. And I'm not gay, either!" There are some men so vile and/or violent that they can easily turn a woman queer, albeit temporarily, and Mr Brown easily qualifies as one of them.

Rihanna's relationship with her "personal assistant" Melissa Forde has added more fuel to the freaky fire. As in the cases of both the late Whitney Houston and the undeniably straight Oprah Winfrey, a personal assistant is often assumed to be a star's girlfriend, travelling and staying with her in the closest of situations. But it probably helps the tongues – of the gossips – wag faster if, as Rihanna did, the star in question tweets: "I'm on my first date in almost two years" along with a photo of Melissa Forde and herself entitled "My lover for the night". Followed closely by "beautiful is great, submissive is even better. Bawse bitch who's submissive yet the captain of the ship n HONEST…" – hashtag #MarryMe. It's so crass, it's class.

You can't imagine Cheryl or Katy getting their hands – or images – dirty to anything like the same degree, and thus their sapphic antics can seem somewhat dead-eyed and desperate. But what if the bluff is a double bluff? There can be no doubt that men get a great deal more out of hetero sex than women do; to put it bluntly, that's why they resort to porn and prostitution in a way that women don't need to.

Repeated studies have show that – to quote one of them – "most men find most women at least somewhat sexually attractive, whereas most women do not find most men sexually attractive at all". That's a lot of sexual shortfall, and who's to say that hidden homosexuality on the part of the female population couldn't be at least part of the reason? What if all those girls "pretending" to kiss girls to turn on boys are actually double bluffing – and are really doing it in order to turn themselves on? What if all those girls who go to strip clubs with their boyfriends are actually getting more out of it than the men do? And what if all those girls who have threesomes aren't doing it to keep their man – but to keep their sanity? In this case, the current crop of apparently thespian lesbians are reflecting, rather than exploiting, the current mood.