And I was entrusted with bringing the most important ingredient for our celebrations. Not the cake, but the cocaine. Five little packets, to be precise, each costing £50 for a gram.

The six of us ploughed through it all over two gloriously long nights. We consumed most of it on the Saturday, after the birthday meal. That's when most middle-aged people start thinking about sloping off to bed but we were buzzing and danced into the early hours, ending up in the hot tub.

As shocking as it might sound, I've been using cocaine for 25 years. In fact, not a single month has gone by when I haven't snorted the drug. Not for nothing am I known as Hell's Bells.

Now 50, I have a high-powered marketing job and am happily married to my surveyor husband, also 50, with a 22-year-old daughter. We have a cottage in south-west London with a gravel drive and a pistachio-green front door and a gorgeous bolthole in Portugal, too. In short, we are the epitome of middle-class privilege.

My partners in crime are much the same: they include a TV director, a banker and even an NHS executive. All successful, upstanding members of the community..

. save for this one illegal habit that we can't quite give up. You'd be right to be shocked given what we're doing is against the law.

But we're far from alone in being middle-aged, middle-class drug users. Cocaine deaths have hit a record high thanks to a surge of middle-aged users, the so-called 'silver snorters' For though cocaine is normally associated with .