A child who lives through a messy divorce will not necessarily be scarred, but Sean Wilsey's chances of escaping without emotional injury were always low. When his socialite parents split up in the early 1980s, it was deemed the most sensational divorce in San Francisco history, leading one tabloid to call Wilsey's mother "The World's Most Expensive Wife", after she requested $30,000 a year for clothes alone. It was, Wilsey writes, "an Eighties prime-time soap opera drama. Except for the pain."

In his compulsively readable memoir, Oh the Glory of It All, Wilsey's focus vacillates between prime-time glamour and private pain, juxtaposing the absurdly gilded world of the Reagan-era rich with the agony of his confused adolescence. Inevitably, the former narrative is the more seductive. Wilsey's parents truly might have stepped out of Dynasty or Dallas. His father, Al, was a butter baron who was given to cruising the Napa Valley in his private helicopter, looking for parties literally to drop in on. His mother, Pat, was the author of the memoir How to Be a Party Girl, a beautiful blonde who eventually dedicated her considerable charm to the cause of world peace, dragging Sean along to meetings with Pope John Paul II and Mikhail Gorbachev. Rounding out the melodrama was Sean's stepmother Dede, a steely heiress who was to wage war against the young author after stealing Al from her erstwhile best friend, Pat.

Although the media have pretty well inured us to the venality of the rich, the unadulterated narcissism of this lot is still shocking. After being abandoned by her husband, Pat begged ten-year-old Sean to join her in a suicide pact; Al packed his son off to wilderness "brat camps" when he became a social embarrassment. Still, Wilsey cannot bring himself to hate either of these ruined specimens, both of whom at least try to love their boy. It is the grasping Dede, whose family made a fortune manufacturing napalm, who serves as the target for the author's considerable enmity (and his best writing).

If even half of what Wilsey credits Dede with is true, she deserves a special suite in hell. When Sean tries to show off his hard-won skill in Italian, she cuts him off with a curt: "The only Italian I need to know is Bulgari." There is an unforgettable, Christmas-morning image of the jewel-encrusted woman, sitting among the "gratification shrapnel" of "rumpled wrapping paper and massacred boxes from Tiffany and Co" while a feeble Al looks on, which reinforces Wilsey's none-too-subtle suggestion that she manipulated her dying husband into denying his children their considerable inheritance.

Compelling as these scenes prove, Wilsey sees them as secondary to his true purpose - that of charting his progress from poor little rich boy into healthy, happily married husband and father. Though the teenage pranks involving stolen vehicles, skateboarding and drugs are familiar, Wilsey invests them with enough humour to keep the reader on his side. Especially well done is his downwardly spiralling career as a high school student. After Dede appears on the scene, he is sent to an exclusive New England boarding school which is little more than a training camp for date rape and cut-throat competition (that is to say, Wall Street). After flunking out, he is sent to a New Age school for underachievers, and then to a horrific boot camp in northern California where counsellors use humiliation to break down the identity of a rebellious adolescent.

Wilsey finally lucks in to a sympathetic school in, of all places, Tuscany, where he comes to understand that his rebellious anger was motivated by an underlying sadness at his abandonment by his parents. At last, the healing can begin.

Though he claims that his emotional wounds have healed, one of them clearly remains wide open - his incandescent hatred for his stepmother. At Al's funeral in 2002, their eyes lock. "She seemed to be saying, I've given your father the grandest funeral imaginable, and now I am done with all of you. I replied, I am going to tell the truth about you. Someone fit a sprig of white edelweiss, plucked from an elaborate, flowered-cross corsage, behind her ear. It was an image from a wedding. Dede smiled and fluttered her eyelashes."

The wicked stepmother got the millions and the mansions, leaving her stepson with only his talent and his contempt. Closing this fine, funny, brutal book, one understands which is the more valuable inheritance.

Stephen Amidon's most recent novel is Human Capital (Viking)