Once seen as the preserve of middle aged men in Utah, or hyper-liberal flower children, non-monogamy is fast becoming the territory of perfectly unremarkable people.

Take Saira Khan. The Loose Women panellist admitted this week, on the ITV programme, that she's given her husband permission to sleep with other women - as she's lost her sex drive.

The former Apprentice candidate said: "I've lost the desire and I find myself making excuses from around 6pm.

"As soon as he comes home, I panic and start saying, "I'm so tired!". I'm embarrassed to say this but I said to him you can go with someone esle if you want.

"I want to make him happy. He'll kill me for saying this... Am I the only one?"

Khan's confession (which her husband has denied) was reportedly met with widespread 'shock'. But it did strike a chord with some, as social media users praised her honesty. And, when it comes to the more liberal world of online dating, she's hardly an anomaly - at the beginning of this year, OKCupid added a new feature that allows couples to search for a third person to add to their existing relationship.

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