Before you start
This is a short book and you can read it in two or three sittings. It's about one habit. Someone suggests a thing, a restaurant, a weekend, a kitchen, a car, a trip for the children, and you say yes, and the yes is about the people and not about the price. You didn't ask what it would cost. You'd have felt odd asking. And at the end of the month there's less than there should be and you can't say where it went, because it went in twenty places, each of which was fine.
I'm going to argue three things. The first is that keeping up makes sense from the inside. You want to belong, you don't want to be the difficult one, and the people around you seem to manage. The second is that the price of an evening is set by whoever chose the place and not by you, that the people you're keeping up with are keeping up with someone above them, that nobody at the table knows anyone's finances, and that friendships don't run on matched spending. The fear of looking tight is a forecast that lands lighter than it feels, and the things bought to match aren't enjoyed the way the things you wanted are. The third is practical. Before you say yes, you ask the price, and you only pay it if you'd have chosen it on your own. Chapters 20 to 23 cover how.
This book doesn't ask you to be frugal, to stop going out, to lecture your friends or to think less of people who spend. It asks one question before each yes, and it separates what you'd have chosen from what you matched.
Two cautions.
If the spending has become debt you can't keep up with, or you're using cards to stay at the table, that's a different problem and it needs a different book, which is the next one in this series, and it may need help now. StepChange, Citizens Advice and National Debtline are free and they don't judge.
And if your income doesn't cover the essentials, this book isn't about you. It's about people who can afford the evening and are spending on evenings they didn't choose. The same three services are the place to start.
The notes at the back give my sources and their limits. Where I'm giving my own reasoning and not a finding, I'll say so.