Have reached the age of invitations, flu jabs, mammograms, and when playing ‘poo sticks’ means a bowel test. Am delighted to be invited, although they tend to lack champagne and never have enough balloons. Remembering the party season when I was a teenager, there seemed to be an invitation every weekend. Mostly Venture Scout discos. Cold, starry nights. Wearing jeans that hadn’t quite dried properly, your mum screaming after you about getting...