The world would be a bleak place indeed without friends.

For many of us,  they often are more important to us than members of our own families.

In the Bible’s Old Testament, King David’s affection for his close friend Jonathan is memorably described as “beyond the love of women.”

High praise indeed.

But maintaining friendships is sometimes as difficult as keeping relationships sweet.

After all you can hardly go to bed and kiss and make up with your best friend.

And just like romantic relationships you can fall in and out of love with friends.

How many times have friendships sprung up in an intoxicating haze only to cool within weeks?

The famously volatile friendship between the Russian novelist Vladimir Nabokov and the literary critic Edmund Wilson is a good example of how things can turn sour.

It is said that they finally fell out after more than two decades of friendship over the precise meaning of a single line of a translated poem.

I still pine occasionally for a male friend of mine from university days who I have not seen for more than two decades but think about almost every day.

To this day I have no idea what caused the rupture of my friendship with him.

My favourite line about friendship though was a long-forgotten one about someone “being at the age when he no longer wished to make new friends”.

Even after hearing it all those years ago I  still cannot decide whether it is incredibly profound  – or downright silly.