Can men and women travel alone together – just as friends? No. Here’s why.

Earlier this year I came travelling to Cambodia with a girl – a friend I had known for ten long years. Our friendship, like many, had grown from a shared circle of friends and relatives.

I had never thought of her as anything other than a family friend – then we booked the holiday, and our relationship changed – or at least seemed to.

In the weeks leading up to the holiday she came to visit me many times, always dolled-up. It was in the deepest winter but she still came in high heels and wore sexy outfits to study the Lonely Planet with me.

She smelled of perfume while sitting next to me when we watched Apocalypse Now to get some jungle feeling. I began to notice how hot she was: all rosy cheeks and killer curves. For the first night in Cambodia we booked a double bed online.

My father warned me it would be a mistake to go away with her, that we would not be friends when we returned. I ignored him.

But by the first night of the holiday I had realised my mistake. Coiled up, she lay next to me in the double bed seemingly fast asleep while I stared at the ceiling, painfully horny.

Those voluptuous liquid curve – so lickable. What a waste. I grabbed all the beers from the hotel room fridge and lay on a sun lounger by the pool.

What went wrong?

Drinking away my itching lust I recalled the devastating and ridiculous conversation we had had at dinner that night.

“Communism isn’t such a bad idea,” she had announced. Here we go, I thought: the communism conversation is her declaration of war on me. Still I took the bait and told her it wasn’t a good idea: history shows it has never worked. “You’re ignorant,” she told me. “You’re stupid,” I replied – and so it went on.

When we ordered the bill, I paid and she wanted to throw in some money. I told her: “Mine is yours and yours is mine. All communist. Let’s give it a shot.”

In the days that followed, falling to bed drunk every night to cope with unsatisfied lust became as exhausting as our conversations. We almost choked each other over talking about gay marriage – me for, she against. She believed that big American companies run the world – I found her ridiculous. I told her homeopathic medicine is mumbo-jumbo while she dribbled litres of different tonics into her breakfast juice. In the end I didn’t want to sleep with her anymore. I couldn’t stand the sight of those curves.

I don’t know what happened to my friend who initially seemed so keen. Had she changed her mind? Was she naïve about sending out signals? Or was she a common teaser?

We stayed together for one week, and then went our separate ways. I wanted some sex on this holiday.

Two days later I got some – with a stranger. The girl and I are still friends but we hardly speak.

The lesson? If you’re going away with a close friend, sleep together first.

Or else it’s an ideal that will float happily in the ether but, like communism, never really works in practice.