Fiction by Liane Moriarty.
This book is full of fun characters and I quite enjoyed it. Here's the premise:
Sophie is a girl who is nearing forty and still unmarried. She is wondering if she should have broken up with that last serious boyfriend (nice respectable boring Thomas), especially since she got along so well with his family. In fact, she got along so very well with his family that his aunt willed her a house, although she and Thomas broke up years ago and he has since married and produced a baby.
Really great book!
I also enjoyed The Husband's Secret by this author.