Friendship, a timeless subject, has never been more debated, something that has to do both with the internet - the perils of WhatsApp groups, the agony of ghosting - as well as with a growing awareness that loneliness is increasing in our society. Friendship has become a matter of urgent inquiry to therapists, scientists and sociologists. We understand its importance more and more, not only as a comfort and a privilege, but as vital to our health. But it's hard to get inside friendship: its particular intensity and its miraculous ease; its tendency to wax and wane; its ability to inspire both delight and despair.

Author: Rachel Cooke