I suspect that, like me, if you think about lonely people you imagine old men and women living on their own. And indeed many old people living alone do feel lonely. However, loneliness in itself isn’t about your physical circumstances. It’s an emotion, and it has more to do with lacking emotional closeness to other people than lacking physical proximity.

This means that some people can feel happy, fulfilled, satisfied despite very little contact with other people. Maybe because of it. Think of hermits, to take this to its logical conclusion, who are not generally perceived as miserable and lonely, because they have chosen their lifestyle themselves.

On the other hand, it also means that there are people who spend lots of their time in company but who still feel lonely regardless. They might be teenagers or pensioners, shy or gregarious, single or married – it’s surprising how many people feel lonely in a marriage that lacks emotional intimacy.

I have one friend who lived on his own for years very happily. Then he met a woman, fell in love and got married. Many years later she died, and he was left alone. He told me that he felt incredibly lonely, despite being in the selfsame situation he had enjoyed living in before he met her. I asked him what exactly had changed and he told me, ‘I know what I’m missing now’. He had found a closeness with his wife he’d never previously had, and he couldn’t stop missing it when she was no longer there.

For a start, this should make it obvious that if someone tells you they’re lonely, you won’t solve their problem for them by telling them to go and join a club (although I hope by now you won’t be telling anyone else what’s best for them). There are some people for whom this does the trick, especially if they make close friends over time, but many for whom it doesn’t make any sense at all.

Many people find it hard to admit they’re lonely. If they manage to admit it, don’t be surprised or disbelieving just because they’ve got a big family, or a busy social life, or a job dealing with people constantly. Anyone might feel lonely, regardless of their circumstances.

Equally, given this section is all about helping people, if you have a friend who seems unhappy and you don’t know why, consider whether they might be lonely, regardless of their circumstances. Especially if the kids have just left home, or their marriage isn’t very happy, or one of their parents has just died.

More people out there than you or I can imagine are lonely, and if we want to help, we need to present ourselves as someone they can really communicate with, not just someone to have a laugh and a joke with – although obviously that as well. Then when they need someone to talk to, and they have the confidence to open up, they’ll recognise us as proper friends who can help them feel a bit less alone.