Despite our willingness to open our house and lives to strangers, our latest home exchange didn't get off to a good start. Only hours after we arrived in France, my mobile rang. At that moment we were feeling rather smug and, even, a little French, filled with crusty rye bread and anchovy tapenade from the local market. It was the father of our French home exchange family. Details of the welcome I had prepared raced through my mind: leaflets of current London highlights – check; homemade lemon drizzle cake – yep; Italian wine ...

And then I remembered a minor detail that had somehow slipped my mind: the keys. I closed my eyes and imagined our French family, and their fears: they had handed over all their precious possessions to English foreigners, who would sweep their rural idyll clean, and then create havoc and abandon it. I frantically got back on the phone, desperate to reach friends with a spare set of keys. Thankfully our neighbours, who are French themselves, were willing to provide a temporary home to these recreational refugees, who were marooned with as much luggage as Ryanair would allow.

This wasn't the first time we had swapped our home with total strangers via a holiday exchange website. Our first tentative try was at the start of 2009 in the home of architect Cedrick and his family – his chic Parisian apartment had African masks on the muted grey walls, and a rich pink bathroom. The following summer we exchanged with Geraldine and her daughters and stayed in their light-filled, terraced Cornish home. Lying in Geraldine's bed with the balcony doors wide open, listening to the River Tamar lapping against the side of her home, was calming and memorable. The fact that these people were strangers lessened the degree of discomfort I felt on intruding into their lives.

But for this latest journey, now a home swap "graduate", I was looking for a way to exchange more than a place to stay. In an email to Nicola prior to the holiday, I asked for names of children that ours could meet and hopefully have fun with. I sought to deploy our offspring as a convenient subterfuge, a socially acceptable excuse to engage with the locals.

It worked. Two days after we arrived in France, we were perched with Nicola's friends on wooden planks overlooking a Languedoc village square watching a traditional dancing and bull blessing ceremony. In another encounter, neighbours Eric and Pascale invited us to dinner – homemade Languedoc fish pie, and local goat's cheese steeped in honey. Pascale later came round to deliver the weekly box of organic vegetables and taught me how to cook a fromage frais and leek quiche.

Though my forgetfulness in the matter of keys might suggest otherwise, my attitude towards house swaps and my trust in strangers had evolved. As internet visionary Clay Shirky argues, the internet gives us opportunities to share with people outside our immediate circle. Trust usually develops over time with repeated encounters, but when you enter into the house-swapping game it is immediate and quite intense – though brief and not usually repeated. What is interesting is the ease with which we felt able to trust this digitally mediated encounter, sharing not only everything we own but also our relationships with friends and neighbours. In essence, we were temporarily swapping our lives.

When we returned home, I felt a little usurped. Our French London neighbours had already been thanked for their hospitality the previous week, with an invitation to dinner around our table.

Then I got this email: "Hi Emily. Thanks to you we exchange not only our home but also the people. When I was travelling around East Berlin in 1990, I felt I was open to the world ... This sensation of connection "partage" is possible thanks to travel and the meeting of the other. Our exchange is the nouvelle experience for the all family. We left the barriers at home and we try to bring back this openness we had in the other home. The kids have been transformed by the English language, culture, and sharing with people. They are rich. Merci, Nicola."

My desire for a deeper encounter had been echoed. A slight blurring of the lines of our separate identities had taken place. One of the ideals of a holiday is to have a transformative experience that lingers long after you return to your daily routine. As we learn to become a little less precious about our separateness, swapping homes and lives may become an increasingly attractive and popular adventure.

• Emily Kasriel is executive producer of The Forum on BBC World Service