Some will tell you they're alone because they want to be, but really they're protecting themselves from anguish they prefer to carry inside.
Some deeply dislike being alone, but the last thing they want is to inspire pity.
They might have been struck with a failed relationship, a family feud, or a move to another city or country where they haven't yet made friends. Perhaps they've recently experienced the death of a life or a rupture with those to whom they felt the closest.
The reasons matter less than the fact that they're lonely.
Many of these people might believe no one really cares, just as they wish on this very day that someone would show that they do.
This, then, is my annual appeal for you to think of your gadget -- on this one day -- as primarily a lifeline to someone else.
Yes, for most of the year, your phone, tablet, or laptop is your source of work, entertainment, and several thousand Emoji'd WhatsApp messages and Tinder swipes.
On Christmas Day, however, think of it as your way to make at least one lonely person feel less alone.
Everyone knows at least one person who'll be spending this day alone. Pick up your gadget and contact that person first.
Whether you know them well or not, it's still worth telling them that you're thinking of them. It's worth it to them. It's worth it to them because they're likely having to endure TV shows, movies, and ads peddling idyllic Christmases -- and I'm not merely talking about Christmases with red-bowed Lexuses appearing in your driveway.
Whoever the lonely person is, use your gadget to say something thoughtful. The lonely see through the formulaic, the bland, and the insincere more than anyone.
Think about what you'd want to hear if you were the one who's alone.
Perhaps you've been there once or more. Perhaps you even experienced the feeling of taking a walk on Christmas Day and looking through other people's windows and seeing them having a good time -- and then walking home to utter silence.
It'll be a friend, a co-worker, a family member, or simply someone you occasionally chat to in a bar or a café. Life can be unremitting in the way it treats the soul.
So pick up that gadget and give the lonely two minutes of your thought.
Just this once, your Snapchats, TikToks, and YouTube videos can wait.