Don't Go by Lisa Scottoline

Dr. Mike Scanlon is serving his country as an army doctor in Afghanistan as this story opens.  He's left behind a lovely wife and baby daughter and he will not be there to celebrate her first Christmas.  It tugs at his heartstrings and he emails his wife and skypes as often as he can.

As difficult as his duties are in Afghanistan, they turn out to be nothing compared to what is waiting for him at home.  His wife, Chloe dies suddently in a freak accident, leaving their family distraught.
Mike returns home to bury his wife and make arrangements for his daughter's care.  While there he learns that his practice has suffered while he was gone and his daughter doesn't even recognize him.
He also becomes embroiled in the mystery of his wife's death, coupled with a secret she kept from him. Faced with mounting difficulties, Mike must garner up the strength and courage to face them all and he does eventually.

This story will motivate you to keep on reading until you unravel who the culprit is.

Ladybookbug!