"Couples who are right for each other don't have the same row"

Underneath the final version there's often a quieter and worse belief, which is that having one row for years is a sign. A sign that you picked wrong, or that something has gone wrong that better couples don't have go wrong, and that the couples you know who seem easy with each other don't have a dishwasher. This belief is why "here we go again" is so hard to say out loud. Saying it sounds like confessing.

I think the belief has it the wrong way round, and I'll give you the reasoning and then some evidence that points the same way. Two people who live together are two different people. One of you wants the kitchen clear before sitting down and the other wants to sit down first. One of you was raised in a house where family came for four days and the other in a house where nobody came. One of you handles worry by talking and the other by going quiet. Those differences don't get resolved, because they're not disagreements, they're the two of you. Put two people together for long enough and the differences will produce a row, and the row will come back, because the differences do. A couple with no recurring row is either very new or not telling you.

Andrew Christensen and colleagues ran a trial of couple therapy with a hundred and thirty-four married couples who were seriously and chronically distressed, meaning years of it, not a bad month. Half got a traditional therapy that works on changing behaviour, the other half an integrative version whose distinctive addition, as its designers describe it, is acceptance, meaning helping each partner live with the differences that aren't going to change. Both groups improved. At the end, seventy-one per cent of the acceptance group and fifty-nine per cent of the traditional group were reliably improved or recovered. Five years on, the two had converged, about half of each group were still clinically improved, and around a quarter had separated. I'm not citing that for the numbers, which are for couples far more distressed than I'm assuming you are. I'm citing it because a whole branch of couple therapy is built on the premise that some differences don't resolve, and that the useful work is living with them, and that premise held up in couples who'd been stuck for years.

So the row isn't a verdict on the match. It's what the match produces. The couples who look easy have one too. What they may have that you don't yet is a way of handling it that doesn't treat every instance as evidence.