When you lose somebody, when you miss them, you suffer because the departed person has become something imaginary, something unreal. But your desire for them isn't imaginary. So that's what you have to fasten onto: the desire. Because it's real.

Jonathan Coe, The House of Sleep, 1998.

The last sleeper I rode was in Vietnam. We (my then-boyfriend David, his mate John, and I) had just left Nha Trang and were on the southbound train returning to Saigon. It was a quiet, subdued journey: we were supposed to be travelling North to Hanoi but the few days in Nha Trang had proved that we had neither the mettle nor inclination to stay in Vietnam. John had seriously gashed his ankle on a piece of flotsam in the sea; I was disgusted by the thousands of condoms generated by Nha Trang's thriving sex trade, scattered by the dozens per meter square everywhere on the beach. Vietnam, though beautiful, was certainly not a day at the beach. The cash-starved, war-hardened people frightened me. After six months of hard work in Kuala Lumpur, we wanted r&r, not hardship, whether witnessed or travailled. This last overland journey had its ultimate destination as the Ho Chi Minh City airport, where a flight to Thailand would take us to rich tourist heaven: Krabi.

The trains in Vietnam were as old and slow as one might expect, and the windows were covered in steel mesh grilles, because as our guidebook explained, children made sport of throwing rocks at the trains. Our sleeper compartment was "first class" accomodation: two small bunks on both sides with thin, plastic-covered foam pads; a small collapsible table; a net curtain, and a door with a broken latch. On the ceiling, a rather ineffectual fan worked on the same dynamo as the ceiling light, which flickered in time with the speed of the train.

I was in an upper bunk across from then-boyfriend David (we found the bunks far too small to want to share, even if we had, which I didn't); Dave's friend John was in the lower, and a Vietnamese couple had the other lower berth.

The journey was long, and I had trouble sleeping. I lay listening to the sounds of the men's breath and soft whispers of Vietnamese coming from below me. The couple spent the entire night clutching one another. It was something curious - their embrace, in a tiny room otherwise filled with three large Westerners, was utterly contrary to the privacy normally sought out for Asian intimacies. Through the night, as I tried to sleep, I could half-hear soft syllables of Vietnamese between the rhythmic clacketing of the tracks.

It was so hard to sleep. The air seemed damp and muggy even as cold breezes blew in through the grille. I pulled my sarong around me but it didn't help much. Nor did it help as morning dawned and the mosquitoes started biting and buzzing in my ears as if they were doing it on purpose.

As we left the countryside and entered the outskirts of Saigon, the tracks became lined with shacks and shops, their denizens using the rails as their main street. Gap-toothed children brushing teeth and taking baths in bright plastic tubs, waving dripping arms at the train. Sinewy young men with towels around their shoulders striding purposefully through the smoggy morning air, utterly ignoring the hundreds of tons of slowly moving steel that cruised alongside them. As I watched the scene I swatted yet another mosquito, swearing quietly so as not to wake my friends.

"The mosquitoes are terrible, just terrible", said the man in the bunk below me, in an American-accented voice. I was astonished. Hardly anyone we'd met in Vietnam spoke English; even the interpreters were difficult to understand. We started talking, pleasantly, if formally, he asking where I was from, I asking what he did for work, thinking that he must have quite a good job to be that skilled in English.

"I live in the United States", he said, with pride or contempt I couldn't tell. "I used to work for McDonnell-Douglas; they arranged my green card. Now I own a store in Michigan".

I asked if his wife lived with him, almost not bearing to hear the answer I expected.

"No, she wants to stay in Vietnam. She does not know any English." The woman, young, pretty, smiled at me.

It was the first smile in ten days in Vietnam that I could be sure was not motivated by profit. She had clear eyes, a kind face. Knowing how long and expensive flights were, I asked (again reluctant, even as I asked, to hear the answer) how often he visited. He said he made it out every year, maybe every two years, if money was tight. This visit had lasted a month.

"When are you going back?" I asked.

"This morning", he replied.

I guess the aghast expression on my face amused him; I imagine it was probably unusual for this man to experience sympathy from someone like me - he laughed, quietly, kindly. I sputtered, "would you like to be alone, the rest of the time-" I looked at my watch; there was only about half an hour to go. He assured me that no, that wouldn't be necessary, reminding me that my friends were asleep in bunks we had paid for. I got up out of my bunk, making noises about needing to wash.

I lingered in the aisle, watching from the other side of the train the rail-track world of kitchens billowing steam and the smells of breakfast noodles as Saigon rolled by. I thought hard. The couple in the compartment, still in their embrace, proved to me that it was possible to live apart from one's love for as long as it took. Modern tags like "long-distance relationship" do true love a disservice, I thought. And then I felt ashamed of myself - the fellow David in the compartment, supposedly my boyfriend, was not my love - I knew that. He was a good guy, someone in whom I sought little more than company, which, I knew, upset him. Though I'd tried so hard to forget him, I knew who was my love. Though he was halfway across the earth, doing who knew what, I was strangely comforted by the thought of him.

I went back into the compartment where my ex boyfriend and his friend were awake and stuffing clothes into their backpacks. With as much diplomacy and grace as I have summoned for any ambassador I bade the man a safe trip, wishing he and his wife a long and happy life. I knew the same diplomacy would be necessary with David, and told him something similar over dinner that night in Thailand .