The things to watch before you marry him

Watch how he behaves when things are mildly inconvenient. Not tragic. Inconvenient. The flight's delayed, the restaurant lost the booking, the shelf he's assembling has one screw missing. A man's character doesn't reveal itself in a crisis, because most people rise to a crisis. It reveals itself in the twelfth small annoyance of a long Tuesday.

That's the thing you're actually choosing. Not the version of him that shows up for dinner with a plan and a clean shirt. The version that lives in a house with you for forty years, mostly on ordinary days.

So the practical question is how you get to see that version before you've signed anything.

Give it four seasons

You need about a year, and you need to have been through a few different kinds of week together. A holiday. A deadline. An illness, even a bad flu. A funeral if life hands you one. A period where you were the difficult one.

Twelve months isn't a magic number, it's just how long it takes for someone's ordinary self to get bored of performing. Most people can hold a presentation together for three months. Very few can hold it for a year while tired.

If you're being pushed to decide faster than that, notice who's pushing and why. Urgency is sometimes love. It's also the oldest way to stop someone from thinking.

Watch him with people who can't do anything for him

This is the single most reliable window you get.

How does he speak to waiting staff, to the person at the airline desk, to his own mother when she's repeating herself? How does he treat a junior colleague who's made an error that costs him an evening? How does he talk about an ex-girlfriend who hurt him — with grief, or with contempt?

Kindness to you proves very little on its own. You're the one he wants. Kindness to someone who has no leverage over him is the real signal, because there's nothing in it for him.

And listen to how he speaks about women in general when he thinks he's among friends. Not the careful version. The tired, joking, 11pm version. That one's load-bearing.

Small promises, kept

Look at the gap between what he says he'll do and what he does. Small scale. He said he'd ring at seven. He said he'd sort the insurance this week. He said he'd stop scrolling after one episode.

A man who keeps small promises to you is very likely to keep large ones, because the habit is the same habit. A man who only keeps the ones with an audience is telling you what he's actually optimising for.

Related, and underrated: does he do unglamorous work without being asked or thanked? Bins, bank calls, the boring administrative sludge of adult life. Someone has to do it, forever. If it's always you now, it'll always be you later, and later includes small children.

How he fights, and how long it takes to end

Every couple argues. What matters is the shape of the argument and the speed of the repair.

Things to look for:

• Does he stay in the room? Not stonewalling for three days, not storming out, not going quiet and punishing.
• Does he argue about the thing, or about you? "You never told me" is a disagreement. "You're exactly like your mother" is an attack, and it's designed to wound rather than resolve.
• Can he say he was wrong, in plain words, without it costing him three days of sulking?
• Does the argument end? Or does it get filed, to be reopened in eight months as ammunition?
• Does he make you doubt what you saw and heard? Sustained and deliberate, that one's serious.

A man who can apologise properly at thirty will be liveable at sixty. A man who has to win will make a home you can't relax in.

The lines that don't move

Some things aren't a matter of fit or personality. They're the end of the conversation.

If you're afraid of him physically, even once, even a little, that's not a rough patch. If he controls the money, or who you see, or where you go. If he isolates you from family or friends, especially slowly and reasonably, one relationship at a time. If he makes you responsible for his emotions and punishes you for them. If contempt has become the normal temperature.

None of this improves because you love him harder. It doesn't improve because he's promised, and it doesn't improve because you get married. If any of it is in your life right now, talk to someone outside it — a trusted pastor, a counsellor, a domestic abuse helpline in your country. Say the details out loud to a person qualified to hear them. The point of that conversation isn't to decide anything. It's to stop making the assessment alone, because being alone inside it is what makes it look normal.

Do you actually want the same life

Chemistry and character get all the attention, and then people build a life and discover they wanted two different ones.

Get specific, out loud, before the ring. Children — whether, roughly when, roughly how many, and what happens if it turns out to be hard. Where you'll live, and how near his parents and yours. Whose career bends when they collide, and whether that's permanent or takes turns. Who cares for the ageing parents, because somebody will have to. Faith: whether you're both in it, whether you'll raise children in it, whether one of you is mostly going along.

Agreement matters less than his willingness to have the conversation at all. A man who gets vague, jokes it away, or accuses you of planning too far ahead has answered you. Just not in words.

What matters less than people say

His height. His current salary. Whether he's good at gifts or grand gestures. Whether he shares your hobbies. Whether his family is impressive.

Strip those out and you'll usually find you've been weighting them far above things like steadiness, humility and a capacity for boredom.

What matters more than people say

How he handles his own failure. Not yours — his. The redundancy, the business that didn't work, the exam he flunked. Does he learn, adjust and get up, or does he look for someone to blame and settle in?

Whether his friends respect him, and whether they're men you'd trust with your children.

Whether he's teachable. You can tell inside a month. Offer a mild correction about something small and see what comes back. Defensiveness is normal. Retaliation isn't.

Whether he's cheerful. Not funny, not charming. Cheerful — the ability to be pleasant company at the end of a bad day. It looks like a personality trait and it's closer to a discipline, and over decades it's worth more than almost anything else on this list.

Two or three people, and then your own judgement

Tell the truth about him to the small number of people who love you and gain nothing from your answer. Not the group chat. Two or three. If every one of them goes carefully quiet, that's information, and you already know it is.

Then decide yourself. Nobody else is going to live there.

One more thing, and it's the hardest: notice whether you're more yourself around him or less. Funnier or flatter. Steadier or always slightly braced. You'll have an answer to that within weeks, long before you have an answer to anything else on this page, and you'll be tempted to argue with it for a year.

Don't.