Man try learn why wife suicide. Tries to get dog to talk. Dog only witness.

Fiction. A woman commits suicide by jumping from a tree in the back yard. Dog is the only one home. Husband tries to figure out why she did it. Finds she was talking to psychics. Dog is the only witness. Man learns of someone who has done surgery on dogs so that they can speak. Man tries to encourage his dog to speak. Book delves into wife's psychosis.

The Dogs of Babel.

Oh thank you for your help. That was very fast too, I've been wondering what the title or authors name was for years!