My husband and I were together for 12 years and had two children – but while he was happy with one person, I needed more

It was the hardest thing I’d ever had to say to my husband, Marc. Three years ago, I sat down and told him: “The idea of having sex just with you for the next 40 years – I can’t do it any more.” But I had come to realise that my life was built around something I didn’t believe in: monogamy.

We had been together for 12 years and had two children, now nine and seven. I love being a mother and I set the bar high from the start – cloth nappies and cooking from scratch. But I needed something more in my emotional and sexual life.

Marc’s reaction was remarkable; he agreed to support me and open our marriage to other partners, although it wasn’t really what he wanted. We started counselling to try to identify the best of what we had, to save it and protect it. Sex is a big part of a relationship, but it is only a part. We didn’t want it to scupper us.

If that sounds difficult, it was. I don’t think we could have done it if we hadn’t spent most of our marriage reading, talking and exploring together.

I quickly embraced the dating scene and discovered another side of my sexual self. I enrolled on lots of sites, where you are asked specific questions about yourself and your preferences. It was illuminating: do I like this? Yes. Do I like that? Well, let’s see. They were the kind of questions I’d never been asked before – and had never asked myself.

I became convinced that traditional relationships are like an air lock. You meet someone. It’s amazing and it’s rare, and then you lock it; you shut the windows and doors, and you try desperately to keep it all to yourselves. Then the air turns sour because there’s no oxygen. You might make a sexual mistake on the spur of the moment because you are craving some – any – contact. Why not live in a world where you can have room for that connection, that spark?

I think most people’s reaction was that Marc should have kicked me out. My immediate family have been supportive, although my mother is still ambivalent. We discuss everything openly, and she understands where I’m coming from, but worries that I’m going to end up on my own. If I do, though, it will be because I have chosen that.

People who choose to be polyamorous often do so after delving deep into themselves and their desires, so it runs close to the kink scene, which was also something I wanted to explore. There’s a temptation to think that, had Marc and I explored these things together, our marriage might have worked without opening it up. I’m not sure that it would have, though, given that he wasn’t into it. It can seem quite intimidating, but I was so ready for it. The first time I went to a fetish club, I felt like I was at home – that I’d found my people.

I now have a partner of two years, Andrea. We work as a couple, but we also have sex with friends. He’s the only partner I have introduced to my children. I love Andrea and I’m very lucky to have him, but I don’t want to live with him – we both value our solitude too much. He and I can flirt with other people and ask for their number, but I still feel jealous sometimes. He went away with another woman and, yes, it was difficult.

Facebook Twitter Pinterest Anita, Marc and Andrea, too: ‘I’m not sure our marriage would have worked without opening it up.’ Photograph: Laura Pannack/The Guardian

Meanwhile, Marc and I realised we were no longer compatible. I had changed too much. We still share the family home and parent our children together. We still get on. We have counselling together, we spend Christmas together – we are still reading and learning as we used to. We wanted to keep all the bits that worked.

We have had to learn so much about communicating better, and I think the children have benefited from that. We have explained that Dad needs one person to be with and Mum needs more people to make her happy. The talk is ongoing; we won’t wait to sit them down when they are teenagers, expecting them suddenly to get it. Understanding polyamory is complicated, but monogamy is fraught with ambiguity, too.

You can craft your own polyamory, but I’m not sure I would want more than two or three other partners. I’m hoping two people I met recently will become lovers, but there’s no rush. People assume that I’m constantly having sex, but it’s not as simple as that. I want an emotional and mental connection with someone, so it takes time to build up to that.

Monogamy, meanwhile, feels more like a competition where you need to bag someone before anyone else does. None of that applies in a poly setup, which is incredibly liberating. Think how strange it would be to have only one friend. You can’t get everything from one platonic relationship. Why would you try with one lover?

As my kidults finally prepare to leave home, I consider the pros and cons Read more

But it’s a challenge: you’re swimming against the cultural norm and it’s difficult emotionally, with or without the support of an existing partner. On top of that, the amount of work involved in maintaining multiple relationships, sexual and platonic, is huge.

Andrea and I look to the future, but there are no expectations. We are part of a broader community and we think developing that is more important. Put it this way: I don’t see myself sitting on a park bench at 80 with one other person. I’d like to be part of a group of people, a community. We seem to want a silver bullet for everything. One God. One partner. But life is plural.

Marc’s view

I’d realised for a few years that Anita wasn’t completely happy, so it wasn’t a total shock when she told me she wanted to explore non-monogamy. It was upsetting to hear that what we had wasn’t meeting her needs, but it was very important to me that she was happy. If that meant her exploring a different relationship style, then I would be there to support her.

I did a lot of reading around the subject of ethical non-monogamy. It makes a lot of sense intellectually, but it doesn’t resonate with me emotionally. It didn’t feel right. I was prepared for our marriage to continue, with me being monogamous and Anita having other partners, but that proved more difficult than we envisaged.

I completely support Anita. I’m glad she has been able to share with me what she’s discovering about the honesty and communication needed to make polyamory work. It’s also true of monogamous relationships, and I hope to take what I have learned from this experience into my future relationships.

What I have always wanted – and still do – is to be with one partner, long-term, with whom I can share all of life’s rich experiences, to enjoy the journey and the inevitable changes together.

Anita and Marc have been amicably separated for over a year and continue to co-parent their children.

• As told to Camilla Palmer

Appetite, a novel by Anita Cassidy, is published by RedDoor at £8.99. To order a copy for £7.64, go to bookshop.theguardian.com or call 0330 333 6846.

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