The officious woman who eventually answered wasn’t helpful and I knew, as she spoke of full flights, financial penalties and credit card details, that my emotional dam was ready to burst. Finally, once I’d grudgingly been granted a seat on the four o’clock flight to Geneva, which would mean throwing everything into my holdall immediately and taking a taxi to Heathrow, I sat down on the bed and stared for so long at the sprigged wallpaper that the pattern began to dance in front of my eyes.

‘He’s gone,’ I whispered, ‘gone forever. I’ll never see him again.’

Expecting the spoken words to provoke a raging torrent of tears, I was surprised that nothing actually happened. Instead, I sat there numbly, my head still full of practicalities. The thought of telling my sisters – all five of them – was horrendous, and I searched through my emotional filing system for the one I would call first. Inevitably, it was Tiggy, the second youngest of the six of us girls and the sibling to whom I’d always felt closest.

With trembling fingers, I scrolled down to find her number and dialled it. When her voicemail answered, I didn’t know what to say, other than a few garbled words asking her to call me back urgently. She was currently somewhere in the Scottish Highlands working at a centre for orphaned and sick wild deer.

As for the other sisters . . . I knew their reactions would vary, outwardly at least, from indifference to a dramatic out-pouring of emotion.

Given that I wasn’t currently sure quite which way I would go on the scale of grief when I did speak to any of them, I decided to take the coward’s way out and texted them all, asking them to call me as soon as they could. Then I hurriedly packed my holdall and walked down the narrow stairs to the kitchen to write a note for Jenny explaining why I’d had to leave in such a hurry.

Deciding to take my chances hailing a black cab on the London streets, I left the house, walking briskly around the leafy Chelsea crescent just as any normal person would do on any normal day. I believe I actually said hello to someone walking a dog when I passed him in the street and managed a smile.

No one would know what had just happened to me, I thought, as I managed to find a taxi on the busy King’s Road and climbed inside, directing the driver to Heathrow.

No one would know.

Five hours later, just as the sun was making its leisurely descent over Lake Geneva, I arrived at our private pontoon on the shore, from where I would make the last leg of my journey home.

Christian was already waiting for me in our sleek Riva motor launch. And from the look on his face, I could see he’d heard the news.