I grew up in Kenya and was nine when we went camping by the beach in Mombasa, with two other families. The constant games and laughter were new to me, as we were a quiet, rather insular family. I went bodyboarding, watched crabs emerge from holes in the sand, climbed all over rusty cannons in the old fort and bought colourful strips of kanga fabric in the market to make sarongs.

One day, my father asked some fishers to take us to the reef in their canoes. It was a good mile offshore: I wanted to stay behind with Mum, but Dad fixed me with a look and said: “You’ve got no sense of adventure, have you?” Then I knew I had to go, clambering shakily into the wobbly wooden construction, clinging on to the sides for dear life.

Returning from that horrifying adventure (bobbing about on the Indian Ocean in quite a swell, with my mother a tiny anxious dot on the distant shore), all the other kids rushed off to the playground nearby, climbing up high rope structures and screaming at the fun of it all.

But I’d had enough of all of them – and of Dad, too. A little way off the beach, I had spotted a white stone tower, its castellated crown hidden in the palm trees, so I headed to it. There was no one around, and it was exciting to discover that there was a low entrance leading to steps that spiralled up towards the top. It wasn’t a very tall tower – about the height of a palm tree – and soon I was up there, on a flat roof with a great view. I lay there on my stomach, enjoying the feel of the palm leaves as – blown by the breeze – they swished across my back. In the distance, I could hear the shouts of my new friends, but I felt completely content, away from them all. I had the feeling then that perhaps life was best when you were on your own.

As I grew up and we returned to live in England, that feeling persisted. I realised I just didn’t enjoy being part of the crowd, the sports teams, the school disco. Boyfriends came along, university, work and travel – but it was always the same: I would heave a sigh of relief when I got to be by myself. There was no doubt that I was happier on my own.

In my late 20s, I discovered running. Great! A sport I could do alone. All I had to do was put on my trainers and leave the house. I entered some races – but it was the solo running that was most enjoyable.

In my 30s, I joined some group adventure holidays, fearful of going to certain new places alone. But I hated hanging around with others, waiting for the guide. I wanted to go off on my own. There was a glorious moment at Abu Simbel in Egypt, when all the hordes had left the temples to rejoin their coaches – and I ran back inside for a last exhilarating moment there on my own.

Then I took a solo trip back to Kenya for a month, wandering around my old haunts in a haze of nostalgia and taking the bus to Tanzania to climb Mount Kilimanjaro. I had to have a guide for that, but he made sure I reached the summit on my own: what a moment!

In 1999, while working as a freelance editor, I flew to Australia and met a man – a connection that was to last for four years. But this worked because I could come and go, flying in when I could afford it. While he worked all day, if I had no work, I would visit beaches with a book or take the ferry to Rottnest Island or mooch around the markets in Freemantle’s old boat sheds. I was always happiest doing my own thing. The weather probably helped.

During my travels, I often thought back to that day of the white tower. Discovering I loved being alone up there made me the person I have become and inspired me to go after the adventures I have had. But I also remember watching a video of a 100-year-old woman being asked her advice on how to have a long life. “Don’t get married,” she replied, without missing a beat.

I have many friends of course, and I do envy them and their families sometimes; but in the end, I think being alone is a price worth paying for the absolute glory of being free – to do what I want, when I want, always.

In Spite of Myself by Mary Fogarty is published on 12 June (Bradt Travel Guides; £9.99). To support the Guardian, order your copy at guardianbookshop.com. Delivery charges may apply

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