Lauren Henderson: Exes Anonymous (2005)
From the Publisher:
For some strange reason her best friend Davey doesn't agree. He thinks Rebecca needs help with her Patrick obsession. And so they set up Exes Anonymous - a self-help group for the unceremoniously chucked. The seven broken-hearted members soon become friends, meeting at each other's flats to swap stories and offer support. Rebecca begins to hope that she can beat her addiction after all. But love hasn't quite finished with Rebecca. After all, it is a hard habit to break...
Lauren Henderson: Exes Anonymous. Time Warner Paperbacks, ISBN: 0751535672 (April, 2005), 345 p., £6.99