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.

In some ways, it feels like a natural next step. But what does it actually mean to have an 'open relationship' and introduce a third (or fourth) party into your romantic lives?

When I first started dating my fiancé, we discussed how we saw things working with regards to other people.

Did we want to be open (able to have sex with other people)? Poly (able to have relationships with other people)? Or did we want to embrace monogamy? Seeing as we’re both naturally monogamous - and averse to the drama and complications that can come from open relationships - we decided to keep it simple and stick to just seeing each other.

But I have dipped my toe in the poly pool before.

It’s no longer such an unusual conversation. More and more of us are dating multiple people, at the same time, before deciding to become exclusive. It’s a trend that seems to have come from across the pond – where, stereotypically, the New York dating scene, sees single people date numerous potential suitors.

While the bulk of my contemporaries have settled in to monogamous relationships, the discussion has often taken place. Increasingly, the response to “shall we have an open relationship?” isn’t “he just wants to shag loads of women.”

Think-pieces about polyamory have tended to be written in active defense. I understand that the much maligned practice needs all the good PR it can get - but it does the lifestyle a disservice to pretend that it’s all rainbows, flowers and great shags.

Some non-monogamous people would have you believe that it’s a perfect harmony, just more love to go around between more people who all enrich your life. From experience, that’s just not the case. I spent the best part of five years in a polyamorous relationship and it was - like all relationships - a mixed bag.

One of the best things about the poly world is having more of you. Two people playing a board game can be boring, but with four it’s fun. Same goes for picnics, holidays and parties. You’re not just a couple, you’re a ready-made group and there’s something brilliant about that.

When one of you is feeling down, there are more people to cheer you up. You get more birthday presents, more sex, more laugher, more of everything. But when I say everything, I mean everything.

When you bring another person into your relationship, you bring all their laughter, joy and cute little foibles. You also bring their insecurities, needs and fears.  It’s a little different in open relationships, where the emphasis is on sex rather than dating, but either way: by introducing another person in to your relationship you get their good days – and their bad days, too.

The first thing people ask you when they find out you’re poly is: “don’t you get jealous?”

To which the answer is “yes, of course.” I infuriated my ex-partners with my unhappiness. But I was fighting a losing battle as a fundamentally monogamous person trying to fit in to a poly mould.

Of course, naturally open people experience jealousy too, but they also experience ‘compersion’ - a word coined by the open community to describe the feeling of joy that comes from knowing your partner is happy with someone else. 

I learned a lot from my experience of polyamory, even if most of that was that I didn’t really want to be poly.  

People in open relationships tend to be brilliant at communicating, either by nature or by necessity. When you involve other people in that relationship, you complicate it - both emotionally and logistically, meaning a much higher level of communication is needed for things to work.

It’s something that, when I stopped being poly, I took forward into my next monogamous relationship. 

Poly people will often tell you that monogamy is unnatural. I think they’re wrong. What they mean is that for them it is unnatural. Just like gay men and women who, once upon a time, got married because it was expected, those who are naturally non-monogamous have historically straight-jacketed themselves into monogamous relationships that fundamentally worked against their nature, making them unhappy.

So I’m tentatively please that open relationships are getting more air time. Hopefully, it’s another step in a direction that sees people accepted for their fundamental natures – rather than having to comply with society’s expectations for the duration of their sexual and romantic lives.