After splitting up with her husband, Sylvia Brownrigg faced a dilemma. Should she tell her children about any new relationships, or her past one with a woman? Would they even be interested?

A couple of things are reliably true about kids: they start out being wonderfully self-centred; and they don’t – they really DO NOT – want to imagine their parents having sex lives.

Every parent has seen the egocentrism that the Swiss psychologist Jean Piaget identified in childhood development. And there is a certain bitter sweetness when they leave that stage behind, coming to see you as a separate person from them (which explains the otherwise baffling fact that you don’t share their love of trampolining, or Katy Perry). And although families vary on the degrees of physical intimacy shared during young childhood, outside of lurid melodramas or the current US president cracking jokes about dating his daughter, most parents recognise the necessary boundary between parents’ romantic lives and their offsprings’.

But where does that leave recently divorced parents as they begin to sketch the shape of their romantic future? Do parents who have been married several times mention earlier unions to their children, or leave that information until their kids have grown up? How do you walk the line between excessive confessions, and springing a surprise on your kids?

My husband and I were together for 14 years. We raised his eldest son until he went off to college, and our two children, who are now in their teens.

Before my marriage, I had a female partner. I did not hide this aspect of my life – in fact, my novel about a passionate affair between two women at college was published the same year our son was born. (Admittedly, I was less attentive to that book’s publicity campaign than for previous books, although my husband kindly came with me to the ceremony when I won an award for best lesbian romance. I thanked him for being my beard.)

But novels seem to be, for most children of writers, in the same category as tax returns in a drawer: the telling information is there, where they could find it, but why would any kid go looking? They don’t want to know.

When my stepson was a teenager, there was a homophobic incident among his schoolfriends, and I wondered how to talk to him about it. I wanted to communicate not just that it was wrong to use insulting epithets about vulnerable (gay) people, but also my feelings about the situation. Yet if I chose this moment to reveal my history to my stepson, I would have to give similar information to my own children, so he would not have the burden of knowing some kind of secret. It seemed to me that my own kids were too young for this (about eight and five), hence my dilemma.

In the end, I took my stepson aside one day, and privately told him about one night when I was in college, and left a bar late with a friend. A bunch of guys shouted “Dykes!” at us, and chased us part of the way back to our apartments. It was frightening and humiliating. My stepson soberly absorbed this tale. I skipped over the fact that the epithet, although cruel, had been accurate.

Six years or so later, my husband and I split up. It was not a break occasioned by a new involvement on either side, but it was nonetheless painful. After the chaos and distress of our transitional year, the dust was settling, and we had both begun dating again.

The irony of feeling furtive with my adolescent kids about my ­romantic life wasn’t lost on me

I had no idea how to navigate this territory with older kids in the house. The family mediator’s wisdom was that you should not introduce a new partner until a relationship was deemed “serious”, but discretion in this era is harder than you might guess, as I learned one evening when I was out at a pleasant dinner with a kind man. My mobile phone rang. When I saw that the call was from my home number, I answered.

It was my son. “Are you on 58th Street in Oakland?” he asked, not exactly in an accusatory tone, but with a sleuth’s satisfaction. Unnerved, I affirmed that I was, and my son explained that he had left his mobile in my car, and had used “Find my phone” to trace its location. He had gone as far as to look, on Google Earth, at the facade of an unfamiliar apartment building. “I’m having dinner with friends,” I told him, pluralising the situation as if that would make it more innocent. The irony of feeling furtive with my adolescent kids about my romantic life was not lost on me.

Sometime after that, I went out for dinner with a lovely woman, and felt a spark between us. Would this, I wondered, be an easier or harder sell for my kids? Two things lessened my anxiety about the question.

One was talking to my friend Jackie, who had been divorced from her wife for a couple of years, and who helped me to see that I was probably overthinking the issue. When I asked if her young son was surprised that she had a new boyfriend, she laughed. “I have never made it a big deal, and he doesn’t have any preconceived idea that you have to be one thing or the other.” Jackie is open and relaxed with her son, and that seems to take the potential charge out of her new configuration.

And after all, in this era and in cities such as San Francisco or London, gender and sexuality are considered fluid; teenagers eyerollingly lecture their mothers on how to be more trans-sensitive and schools like my children’s hold discussions on equality and sensitivity.

It became clear to me that discussing my past was less important than simply being straightforward with them, as and when I could be, about our future. However, just as I realised that, something else happened: an opportunity arose. My 12-year-old daughter and I were travelling together. Both she and my son had a vogue for “Would you rather …?” questions, which often initiated interesting quasi-philosophical conversations over the dinner table. (“Would you rather be invisible, or be able to fly? Would you rather have to do all your movements as dancing, or speak all your words as singing?”)

One morning, my daughter told me about a “Would you rather” that had been circulating among her friends. “If you could time-travel, would you rather go back to an earlier self and tell her something you know now – or go ahead to a future self and find out what is ahead?”

My daughter tactfully conceded that, because of my age, the question was weighted differently than for her and her friends, who might have more room to be curious about the future than the past. Still, I thought about it for a few minutes, then answered.

“Well, I’d go back to when I was about 18. I had a girlfriend in college, and when I told my mom – your grandmother – about that, she was really upset at first. Things were difficult between us for a long time.”

My daughter was listening.

“So, if I could, I’d go back to my 18-year-old self and tell her, ‘It’s OK, you and Mom will work it out. She’ll become more understanding and accepting about your life and choices, and you’ll end up being really close.’”

I hadn’t asked for a chance to explain my past, I just got luckywith my daughter’s game; but it gave me the opportunity to tell her what was important, in a few sentences – about an earlier time of my life, and an aspect of mother-daughter relations.

Later, when it was time for me to talk to them about a new relationship, they would nod, absorb the information, and then, like any children having even briefly to consider their parents’ romantic life, do the obvious thing. They changed the subject, and started talking about something else.

• Pages for Her by Sylvia Brownrigg is published by Picador, £14.99. To order a copy for £12.74, go to bookshop.theguardian.com or call 0330 333 6846. Free UK p&p over £10, online orders only. Phone orders min. p&p of £1.99.