What staying in costs

You may think of the habit as costing the odd missed night out. I think it costs more than that. Most of this chapter is my own reckoning.

Friendships. Friendships are kept alive by time spent together. If you see someone twice a year because you cancelled four other times, the friendship gets thinner, however fond of each other you are. Nobody quarrels. You just have less and less of each other's lives in common.

Work. A lot of working life runs on small familiarity. People get thought of for the interesting project because someone chatted to them at the summer party. Disagreements are easier to settle with someone you've had a drink with. Skipping every social event at work doesn't get anyone sacked. But after a few years of it you're known less well than the colleagues who turned up.

The occasions that don't come round again. This is the cost people regret most, in my observation. It's the wedding you found a reason to miss, or the retirement do for someone who'd been kind to you. The relief lasted an hour, and the absence can't ever be undone.

The people at home. If you have a partner, they've either been going to things alone and explaining your absence, or they've stopped going. If you have children, they're watching how an adult responds to an invitation.

A shrinking map. Avoidance spreads. It begins with big parties and moves to small ones. Then it's phone calls, which become texts. After a while it's the shop where the assistant is chatty, or the school gate. The NHS list of signs of social anxiety begins with worry about everyday activities such as meeting strangers, starting conversations, speaking on the phone, working or shopping. People don't usually start there. They get there in stages, and each stage seemed reasonable when they reached it.

What you think of yourself. Every excuse is a small untruth told to someone you like, and part of you keeps count. You also gather evidence, week by week, for a view of yourself as someone who can't cope with ordinary things. That view is wrong. It rests entirely on evenings you didn't attend.

The evenings themselves. I've left this until last because it's easy to forget. Some of those evenings would have been good. You missed a conversation you'd have remembered, a friendship that might have started, and a night when you'd have laughed until your face hurt. The habit never counts any of that. The evenings you stayed in for are mostly ones you couldn't now tell apart.

Against all that, the habit has given you a few hundred separate hours of relief, and each one made the next dread heavier.