"If they wanted to see me, they'd ring"

Start with the argument from evidence, because it seems the most hard-headed. People do what they want. They haven't rung, and you draw the conclusion that they don't want to.

The trouble with it is that the same argument is available to them. You haven't rung either, and you've had the same fourteen months they've had. If silence proves lack of interest, then yours proves it about you. Yet you know perfectly well that you'd love to see them. You thought of them warmly this very afternoon. Your silence doesn't come from indifference. You were hesitant, the tally was in your head, and you had a vague sense that too much time had passed.

So you already have a complete explanation for fourteen months of silence from someone who cares, because you're living it. The only question is whether your friend is more likely to be silent for your reasons or for the cold reason you've assigned to them.

Lara Aknin and Gillian Sandstrom have studied exactly this, in a series of seven studies with more than two thousand people. Most people they asked had an old friend they'd lost touch with, and most expressed little interest in getting back in touch. That could look like support for the cold reading, until you see the next part. In two of the studies they picked out the most favourable case. The participants said they wanted to reconnect with the friend and believed the friend would appreciate hearing from them. They had the contact details to hand. The researchers gave them time, there and then, to write a message and send it. Fewer than a third did.

These were people who wanted to, thought it would be welcome, and had the means and the time, and still two thirds of them didn't press send. In another study the researchers asked people how willing they'd be to do various things. Getting in touch with an old friend came out level with talking to a stranger. On average people said they'd be more willing to pick up litter, though not every difference on that list was statistically reliable.

This changes what your friend's silence can tell you. In Aknin and Sandstrom's studies, silence was what most people produced even when they felt warmly and wanted contact. It's the default. It's what happens when nobody does anything, and nobody doing anything is the normal state of affairs. The silence is what you'd see if your friend had gone off you. It's also what you'd see if your friend is sitting on their own sofa on a Sunday and passes your name. They'd feel a pang, think that you haven't been in touch either, and look for the plumber.

It's like two polite people at a doorway, each waiting for the other to go through first. Neither is being cold. If neither moves, though, they'll both be standing there for a long time.

There's an objection. "But some people really have moved on. Not everyone wants to hear from an old colleague." True. Some have. My point is that silence can't tell you which kind your friend is, because both kinds are silent. The only thing that can tell you is a message and what comes back. Chapter 14 deals with what to do when what comes back is nothing.

I'd add one thing from my own reasoning. Somebody has to go first, and it may as well be the one who's read a book about it. Your friend is stuck in the same wait as you, and they haven't had it explained to them. If you hold out for them to break it, you're asking them to do something that two thirds of willing people don't manage, and treating their failure as a verdict on you. If you break it yourself, you'll know within a day or two where things stand, and I think there's a good chance you'll find that things are where they always were.