Nine years ago, a friend from my childhood in South Africa visited me in London. She reads Tarot cards and energies and offered to assess me, hovering her hands over my body, starting with my head.

“Wow, you have a lot going on there,” she said. Her hands then hovered over my heart. “Here is a strong center of energy also — your love for your family and friends.” After moving her hands lower, she said, “From the waist downward I’m detecting no sign of energy. Nothing.”

I was 45, stable professionally and personally, married with two children. But my husband, Colin, a writer and professor of English literature, was 34 years older than me. I had fallen for him so utterly when he was my landlord almost two decades before that I had given up the sunshine and wildlife of Africa to settle with him in London.

Now he was turning 80, and our age gap was showing. However fit and healthy he was, no one can evade biological aging. Our love was strong, but our sexual relationship had ended.

My friend’s assessment saddened me, like something in me was dead. But you can’t have everything. Colin and I had a rare intellectual compatibility that we always called, from Shakespeare, a “marriage of true minds.” I valued our life together so much that I believed I had come to accept the absence of a physical relationship.

Until I went to a class called “How to Have Better Conversations” one night, a week before Christmas, and a tall, attractive stranger asked if he could sit next to me. I noticed there were rows of empty seats all around. I said yes.

During the class, the presenter emphasized how boring it was when people meet someone new and say, “What do you do?” He ended the class with a thought-provoking question: “What conversation are you not having, and with whom?”

After the class, the attractive stranger — Richard — invited me for a drink. He suggested we implement something from the class and not ask, or tell, each other what we do.

That seemed to me a fun experiment. He was not based in London. We exchanged email addresses.

Richard and I started emailing each other daily. He was a bit younger than me, and a full 40 years younger than Colin. He had never married or had children. He said we could be friends.

But when we met again, we kissed. A long dormant energy stirred. I realized I could no longer ignore this side of life. I had to talk to Colin. This was the difficult, painful conversation I had not been having.

What happens in wildlife, when the male primate or elephant or lion ages? A younger rival contests him for his place with the female, and they fight, even to the death. Or the elder is ousted from the group and wanders off alone. The difference with humans is that we can have conversations about these things. We can make unique decisions.

Colin and I agreed our main values were to continue sharing our lives and to keep our family intact, both wanting to maintain daily co-parenting of our children. But we agreed that I could, discreetly, cease being sexually faithful to the sexless marriage.

Richard and I became lovers. A thrilling, midlife, erotic reawakening unfolded. We would meet up late at night in my office, after everyone else in the building had gone, and make love until dawn. We still did not tell each other our careers (although my office offered clues).

One day Richard proposed to me hypothetically: If I were free to marry him, would I?

“Yes,” I said. “I would.”

Eventually, we arranged for Richard to come to our house to meet Colin and the children, as a friend. Two weeks later, Richard had a conference to attend in London.

“Now that Richard has met the family,” I said to Colin, “could he stay in our guest room while in London?”

The next day I was out in the garden with friends when we decided to order a late-lunch pizza delivery. I went into the house to call Colin to join us. To my shock, I found him in a darkened room, still in bed, at 2 p.m. I had never seen him like this before. Suffering.

“This is all going so fast,” he said. “I’ve only just met Richard and now you’re asking if he can stay as a guest in the house.”

“Do you need me to stop seeing him?”

“No,” he said. “I am the past, Richard is the future. Promise me that if you’re thinking of leaving him, you will first discuss it with me?”

Colin was thinking ahead, to a time when our family would be without him. It’s like he was making a succession plan. Through tears, I nodded.

Richard and I agreed the time had come — eight months since we had met — to finally tell each other what we do.

“Rather than tell you,” he said, “I want to show you.”

Early one morning he picked me up and drove to the countryside. He stopped the car by a field. “This is what I do,” he said.

I was baffled.

“I’m an agronomist,” he said, explaining that he advises farmers on how to use their land, what crops to grow and how to care for them.

More than that, he specializes in regenerative agriculture. When establishing a new crop, instead of using toxic chemicals to destroy all that went before, he grows different crops simultaneously, sharing the same field, acting as companions, providing benefit to each other rather than threat. It’s a systemic approach that goes against tradition, and people may greet it with prejudice and challenge, not understanding, and taking a long time to accept it.

When I started telling family and friends about me and Richard, I also met with prejudices and challenges. Some were devastated, warning that this could harm our children, and that I was risking everything for a stranger.

“You don’t know him at all,” one friend said. “There’s a saying in Italy that you don’t know someone until you’ve eaten a kilo of salt with them. Which takes a very long time. A whole kilo of salt!”

After I told Richard about this, he bought me a kilo of salt and said, “Let’s start sharing this, and once we have finished it, no one will be able to say we don’t know each other.”

One night in our favorite restaurant, he seemed preoccupied. I said, “What’s the conversation you’re not having?” He told me how painful it was for him to always feel on the outside of my family life with Colin and the children. They came first for me, and he had no secure place for himself.

I knew it was time for me to have another difficult conversation with Colin.

I explained Richard’s perspective and insecurity. Colin had a legal bond with me (our marriage) and a biological one (our children). Richard had neither. What could we offer Richard to prove to him — and the people in his life, like his parents — that he was not being kept on the outside?

Colin and I acknowledged we would always have our children and our “marriage of true minds,” regardless of whether we were legally married. Richard’s place would be secured if he could marry me. Everything could stay as it was, but we agreed that Colin and I would legally divorce. Divorce was only a piece of paper.

In the UK then, no-fault divorce did not yet exist. One party had to petition for divorce against the other; it couldn’t be a joint application reflecting a mutual decision. And Colin couldn’t cite my adultery as grounds for divorce, because if you continued living with your spouse beyond six months after the adultery was known, you were legally taken as having accepted it.

“Accuse me of unreasonable behavior then,” Colin said. “I’ve certainly done something incredibly unreasonable — I’ve gotten old!”

But there was another hitch. By law, every permissible reason for divorce was based on the same condition — that the two spouses “can no longer tolerate living together.”

Colin and I were still living together, although in separate bedrooms, and we wanted that to continue. The lawyers I consulted said that would not be possible. I decided to represent myself in the case instead and succeeded; our request was granted.

Richard moved in, and three years after we met, he and I began planning our wedding. All five of us were living together companionably, giving benefit to each other, not threat. Friends and family gradually accepted our unusual situation.

And that year at our Christmas Eve party, hosted by Colin and Richard and me, we gathered around the turkey and scattered on it the last few grains of our kilo of salt.

Sonja Falck is a psychotherapist and university lecturer in London and the author of three books.

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