The Third Wife by Lisa Jewell

Adrian Wolfe has been married three times. His third wife, Maya, dies after stepping in front of a bus, and it's unclear whether it was an accident or suicide. 

As Adrian—and the family—grieve, secrets and dysfunctional aspects of their relationships begin to surface. The story moves back and forth in time to reveal Maya’s last months, and also shows how Adrian’s children and his ex-wives are affected.