I wish someone had told me at the time that growing up in Guernsey was extraordinary. Not that I was receptive to that information – I was far too busy dreaming of what else the world could offer. The excitement and glamour of the mainland was too gripping to let me take stock of the privilege of plodding towards adulthood on a tiny island. I took for granted the freedom I had: the slow speed limit that almost guaranteed my safety; the low crime rate; the fact I was never more than 10 minutes away, no matter how much I tried to escape. Guernsey was my playground and yet I spent most of my days staring at the horizon yearning for the energy of the big city.

I was raised by Londoners who moved to the island to set up shop in the 70s. They were more than aware of the contrast to city living – yet I never knew any different. Dramatic cliffs and coast roads, vast sweeping beaches and “island hopping” on ferries was regular life. As soon as I was old enough to pass as 18, the island’s pubs were my stomping ground, of which the walls still hold many of my deepest secrets. As a teenager, I was always more of a town girl than a beach girl, spending most of my time pounding up and down the cobbled high street of the quaintly pretty St Peter Port that clung on to independent retailers and pushed crab sandwiches like America does fast food.

My home parish of St Martins was an idyllic setting for me to tear around on my bike, being told to be home in time for dinner. The entire cliff path was all mine. I knew all the best trees to climb, which cows in the field were friendly and what time the tide was low so I could go winkle-picking in the rock pools. And even then, I didn’t realise I was lucky. I thought other kids were having real-life adventures on trains and high-speed motorways, in huge high schools partying at all-night raves.

When that scene did come to the island, we gave it a good go. I’d shop for velvet hotpants and Buffalo Boots in the one trendy shop (it was called Clobberbox and it’s still there at 2 Market Hill, St Peter Port), and we’d drink cheap wine outside before waving our hands in the air as if we just didn’t care, before making sure we were home by 11pm. I imagined the London version: bigger, louder, cooler. Everything, even my beloved Thursday nights at the small local theatre group, could never quite scratch my itch when I imagined the mainland kids on bigger stages, in bigger shows, living bigger lives. It was all I wanted to do. Get old enough and leave.

But when I did, of course, I quickly came to understand what I had left behind. When I came back to visit there was a memory on every corner, my history carved into the streets. Guernsey became a retreat, the place I’d go to regroup, psyche myself up for the next batch of struggling that life in England seemed to go hand-in-hand with.

Now I return many times a year with my two boys and the things I wanted to escape from are the very reasons I go back. I want my children to know the island, to have the freedom I had. The island has come to life for me again; I see the kids with their little nets trawling the fruits of a low tide. They run, just as I did, along the cliffs of St Martins, panting up the steps, then battling the tricky approach to Marble Bay to swim in the glistening blue sea. We take the ferry to Herm, an even tinier island. Like a green hill in the ocean, it is held in place by vast sandy beaches, a large common, the Mermaid Tavern that never fails you and the Herm Shop, possibly the best gift shop on the planet.

In recent years we’ve added Sark and Alderney to our to-do list. We even managed to visit four islands in one week – a record for me, despite living on Guernsey for 18 years. When it isn’t sunny, there are plenty of other activities. This year I signed my eldest up to Outdoor Guernsey, a wild and wonderful adventure camp, which saw him coasteering, diving off SUP boards and jumping off giant rocks. On one rare childfree day, I wandered into St Peter Port via Hauteville House, where Victor Hugo lived, and grabbed a crab salad and a glass of rosé at the Terrace Garden Café overlooking the marina. Afterwards, I strolled through the market and arcade and found a delightful new bookshop called Writer’s Block, which supports the local writing community.

I stay with family when I am there, but I’m very tempted by the idea of spending a night or two in the Fermain Tower, a unique, renovated 18th-century watchtower overlooking Fermain Bay. Just behind it is one of my favourite places, the Fermain Beach Café, with stunning views across the bay. I recommend the scallop salad with a crisp pinot grigio or a decadent hot chocolate, after a swim in the sea. It doesn’t get better.

Even though real life has settled me elsewhere, I go back to Guernsey in my fiction. My latest novel is the third one I’ve set on the island. Being able to relive those earlier years through the eyes of my characters Renée and Flo is cathartic and in many ways a relief. Seeing the island through grownup eyes has made me fall in love with it all over again, maybe even more than I did before. And I finally realise that makes me very lucky indeed.

For more information, go to visitguernsey.com.

Honeybee by Dawn O’Porter is published by HarperCollins at £20 on 26 September. Order it for £18 from guardianbookshop.com