Sloane Crosley: 'As we grow up, there should be fewer instances of friends you can only take in small doses'

There are certain people I just won't eat in public with anymore. It seems strange to compartmentalise one's friendships like this, especially as an adult. As we grow up, it feels like you should either invite people into your life or not. There should be fewer and fewer instances of friends you "can only take in small doses".

I think the rule of thumb should be this: if you preface a sentence about a friend with the phrase, "I love X, but..." more than once in any conversation, you should stop hanging out with them. I know, I know: you've been friends with this person since you were six, or you went to university with them, or they stopped a meteor from hitting you with one hand while tearing out their own kidney for you with the other. They'd be the first one there to bust you out of jail or the first to send flowers to the hospital. Look at them, being an ideal friend!

But friendship is as much a game of numbers as it is of emotions. There are far fewer bus accidents and meteor showers than there are drinks and phone calls and house parties. It is in these seemingly ordinary realms that friendship has its true home. In my early thirties, I hope I have weeded out the worst of these offenders and I know I have been weeded right back. Not every friendship is a perfect fit, just because it's a little long in the tooth.

I have one friend who comes through brilliantly both in the daily minutiae of life and in its grander scenarios. I am lucky to have her. My only issue? She is unbearably rude to waiters, to the point where I find myself mouthing "sorry" to staff on the way out of the restaurant. I know that they've spat in our food. And I doubt, when grabbing our two plates from the kitchen, they bothered to make sure they gave her the spittle-laced dish, and this is precisely the problem. A friend this rude will drag you and your omelette down with her. It would be impossible to say anything (all hints have failed) without offending her. Alas, our friendship will have to be restricted to phone calls and jail cells. For now, at least. After all, no one wants to eat alone forever.

Sloane Crosley is the author of 'How Did You Get This Number' (Portobello)