Please help me find a book

Years ago I read this book that I am trying to find.  I dont remember the author. The story starts with a PI calling male character and saying "I've found her.  Gist of the story is, they were together and then she disappears.  The PI finds her approx a year later.  She has had his baby and he comes to intentionally take over the company where she works.  The details are a little sketchy after this but I remember when he finds our she had a baby for him (girl) who is at her friends house he puts his hand through the wall and was crying.  I hope this is enough info