Two’s company, three’s a crowd—unless in fiction, when it’s a recipe for page-turning, emotional gold dust. It’s a theme returned to over and again in literature, because nothing else offers quite the same level of conflict, tension or heart-in-the-mouth angst as a good old love triangle.

Obvious examples jump out from the classics; Heathcliff, Catherine & Edgar’s bleak, tempestuous life on the wilderness of the Yorkshire moors in Emily Bronte’s Wuthering Heights, and in Lady Chatterley’s Lover, D.H. Lawrence gave us Lady Constance, Sir Clifford & their gardener, Mellors. Considered too racy in its day, it’s actually a tender study of a marriage in crisis.

Love triangles haven’t fallen out of fashion in contemporary novels, either. I can’t think of Helen Fielding’s Bridget Jones’s Diary without immediately thinking of Mark Darcy and Daniel Cleaver, too. There are few books in the world I love more than Helen Fielding’s “Bridget Jones” novels; I only have to open the pages and I’m fully invested in all of the characters.

For me, its triumph lies in the fact that although Daniel is a complete rogue, he’s lovable and charming with it—we get a sense that he genuinely does harbor feelings for Bridget. Their relationship would have been a complete disaster long-term, of course, but the fact that we can’t help but empathize and love Daniel a little makes the triangle believable. In contrast, Mark Darcy is so terribly clipped and uptight, lacking any of Daniel’s charisma and easy wit; it takes a while to warm to him as the stoic, loyal, quieter hero of the piece.

"I thought about all of these things when it came to writing 'One Day in December.'"

Stephenie Meyer’s Twilight trilogy is a great example of a love triangle with three almost equal sides. As readers, we recognize that both Edward and Jacob have the potential to be Bella’s forever love. For the record, I will always be #TeamJacob. And that is probably the most compelling thing of all about love triangles in fiction; we know that the crunch point has to come, and readers get to nail our hopes to the flag on which way we want it to go. It’s an unpopular opinion, but I still think Bella should have chosen Jacob!

I thought about all of these things when it came to writing One Day in December. I’ve always believed love triangles are at their most interesting when there are no obvious villains or heroes. I wanted to acknowledge that real life IS often messy and complicated, and that sometimes people do the wrong thing with the best of intentions.

The story spans a ten-year period, and over the course of the book there are actually two love triangles in play; the more traditionally romantic one between Laurie, Oscar and Jack, and the non-romantic, but surprisingly complex one between Laurie, Jack and her best friend, Sarah. Early on in the book Laurie chooses not to reveal that Sarah’s new boyfriend, Jack, is the guy whom she fell hopelessly in love at first sight with the year before, thereby placing a lie at the center of their friendship. It’s a selfless decision made out of love and loyalty, and even though it inevitably comes back to bite her, I don’t think Laurie would make different choices if she had the chance to do it again. There’s a pivotal scene where Laurie herself acknowledges the unique nature of this central trio and how the feelings between them have evolved over the years and entwined them forever: I remember the first day I met Sarah, and the first time I saw Jack, and how very tangled and complicated our lives have become over the years. We are a triangle, but our sides have kept changing length. Nothing has ever been quite equal. Perhaps it’s time to learn how to stand on our own, rather than lean on each other.

Many readers have said that the nuanced friendship between Laurie and Sarah is their favorite “love story” in the book, and I admit, I do love the idea that a friendship can have just as profound an impact on one’s life as a great romantic love.