But why must everything always have a practical application? I'd been such a diligent soldier for years – working, producing, never missing a deadline, taking care of my loved ones, my gums and my credit record, voting etc. Is this lifetime supposed to be only about duty?

I have not been fair to him; if anything, I'm guilty of the same offense: trying to keep the life we had from being ruined. Is it a crime when you love someone so much that you can't stand the thought of them changing? Is it a crime when you love someone so much that you can't see them clearly?

Twenty-eight years is a long time to think about why I loved you, and it's not for the reasons I first assumed: because you swam in the space below my heart; or because you stanched the youth I was bleeding out daily; or because one day you might take care of me when I couldn't take care of myself. Love is not an equation, as your father once wanted me to believe it. It's not a contract, and it's not a happy ending. It is the slate under the chalk and the ground buildings rise from and the oxygen in the air. It is the place I come back to, no matter where I've been headed. I loved you, Bethany, because you were the one relationship I never had to earn. You arrived in this world loving me more, even when I did not deserve it.

Bad is not an absolute, but a relative term. Ask the robber who used the cask he stole to feed his infant; the rapist who was sexually abused as a child; the kidnapper who truly believed he was saving a life. And just because you break the law doesn't mean you have intentionally crossed the line into evil. Sometimes the line creeps up on you, and before you know it, you're standing on the other side.

What if memories get stored in the brain, and they aren't even necessarily ones we've had? What if we're hardwired with a whole iceberg of experiences, and our minds use only a tip of them?

Memories aren't stored in the heart or the head or even the soul, if you ask me, but in the spaces between any given two people.

At that moment, everything comes clear. It's like having someone walk up to a chalky window that you've been trying to see through for days, and wiping it clean. Some people have a detailed history, others don't. There are plenty of adopted children who grow up without knowing an once of information about their birth parents; there are criminals who walk out of jail and become pillars of the community. At any moment, a person can start over. And that's not half a life, but simply a real one.

It is also a terrifying prospect: that the relationships we use as the cornerstones of our personalities are not given by default but are a choice; that it's all right to feel closer to a friend than we do to a parent; that someone who's betrayed us in the past might be the same person with whom we build a future.

If it had been easy for Romeo to get Juliet, nobody would have cared. Same goes for Cyrano and Don Quixotye and Gatsby and their respective paramours. What captures the imagination is watching men throw themselves at a brick wall over and over again, and wondering if this is the time that they won't be able to get back up. For everyone who adores a happy ending, there's someone else who cannot help but rubberneck at the accident on the side of the road.

You wonder, though, what would have happened if Juliet's best friend started flirting with Romeo. If Gatsby got drunk one night and told Daisy how he really felt. If any of those poor romantic fools would have driven hours north to the Hopi reservation and doubled back, the word sucker fizzing like acid in their bellies as they sneaked glances across the car at the woman they loved, knowing she was going home to another man.

Could it really be that simple? Could romantic love and platonic love and parental love all be different facets of the same diamond – brilliant, no matter which face is turned up to the sun?

There are two kinds of love. In the safe kind, you look for someone who's exactly like you. It's what most folks settle for. But then there's the other kind of love. Everyone's born with a ragged edge, and some folks crave the piece that's a perfect fit. You'll search for it forever, if you have to. And if you're lucky enough to find it, it looks so right, you start to tear at your own seams, thinking, maybe I could look just as perfect. But then of course, when you try to get close to the other half, you don;t fit anymore. That kind of love ... you come out of it a different person than you were when you started.

I realise, suddenly, that everyone is a liar. Memories are like a still life painted by ten different student artists: some will be blue-based; others red; some will be as stark as Picasso and others as rick as Rembrandt; some will be foreshortened and others distant. Recollections are in the eye of the beholder; no two held up side by side will ever quite match.

The only way someone can leave you is if you let them. And I'm not doing that. It may look like that today, or tomorrow, or even a month from now, but one day you're going to wake up and see that this whole time you've been gone, you've only been headed back to where you started. And I'll be there, waiting. I'm just trusting you enough to come back.

What if it turns out that a life isn't defined by who you belong to or where you came from, by what you wished for or whom you've lost, but instead by the moment you spend getting from each of these places to the next?

Vanishing Acts by Jodi Picoult