David was new to the social networks that had sprung up on the internet in the past couple of years. Just for kids, he'd thought, until one came along that seemed a little more sophisticated, a little more adult.
So he signed up, not knowing what to expect. It became compulsive - loading photographs that might appeal to others aesthetically, feeding in his address book to see if any of his friends from around the world had also given in.
At first it was slow - the odd contact from a long-lost work colleague, even an old girlfriend, now settled down, and - like him - married with a child.
Over the next few weeks his network grew. He began to use it to rebuild old friendships severed by time and distance, adding horoscopes, biorhythms and other bolt-ons to make it more fun.
Then, he received a request for friendship from someone he didn't know. He checked it out - a strikingly beautiful woman with an interesting profile, not simple, not predictable.
That was how it began. They instant messaged each other, talking freely about their personal problems as if they had been friends for years. The words flowed easily - no no-go areas looming between them. An easy social relationship grew.
He learned she lived with a lover, but there was someone else, on another continent, unreachable. The separation and the strains of living with someone who knew she wanted to be with someone else were taking its toll.
He shared with her his own story - of a beautiful woman met under dangerous circumstances. Two journalists with their lives at risk in a distant and strange land, it was not long before love - and then sex - became inevitable.
David and Sophie had two wonderful years of adventures - travel to exciting places, European cities, staking their claim to be the first man and woman to make love on Eurostar as it sped through the Channel Tunnel. They holidayed on the Costa de la Luz near the Straits of Gibraltar, staying in a villa right on the Atlantic Ocean. They enjoyed fantastic sex, they delighted in each other's company, they smoked a lot of grass.
She was half Nigerian and spoke often of wanting his child - she wanted it to be her warm brown colour with his blue eyes. They used no contraception and there were several false alarms.
She travelled independently with her job - to Morocco, to Switzerland. Sometimes the relationship got a little screwed up - once he abandoned everything to fly to Geneva to try to sort out a misunderstanding that threatened to wreck things between them. She had a history of many lovers, simultaneously and sequentially.
For him she gave up that aspect of her wild side - but not others. His love for her was a real addiction.
Once or twice they broke up - he to try to rebuild his relationship with his wife and to be there for his teenaged son. But, like a drug, the attraction was too strong and it was usually not long before they were back together. Until the last time. He had to decide and in the end it seemed to him that he had no choice.
He and Sophie met in a café near Charing Cross where they had a cold, matter-of-fact discussion and they both walked away, neither turning. He knew that Sophie cut off ex-lovers - no "lets be friends" platitude would work for her.
