The Irresistible Inheritance of Wilberforce by Paul Torday

Wilberforce is a computer geek who turns his teenage hobby into a multi-million-pound software business, working long days and spending the nights at home alone with a takeaway. By his 30s, he is rich and successful but restless and bored. When he stumbles into a local wine shop and is befriended by the smart, sophisticated owner, he finds everything that he has been missing: a father figure, a new obsession, interesting friends and a woman to love.

Torday tells the story in four sections, each describing a different year, but he has chosen to reverse the chronology. The book begins with Wilberforce as a befuddled drunk, staggering around Mayfair, drinking 250 units of alcohol every week. His wife is dead, his friends have deserted him and he is losing his grip on reality, regularly slithering into weird hallucinations about a kidnap in Colombia.
By the end of the novel, Wilberforce is a hopeful young man, embarking on a new and thrilling phase of his life. He's never drunk much except Diet Coke and the odd beer, but now he's learning how to taste wine. For the first time in his life, he's made some friends and even entered the charmed circle of the ridiculously wealthy. He feels sure that he's on the brink of great things.
This is the complete antithesis of Salmon Fishing in the Yemen, its dark take on addiction does not produce many light-hearted moments.  At the end of the book I found myself disliking Wilberforce for wasting his life in such a manner which I guess was a result of being completely drawn in by the story. 

Very readable