I think he wrote the book about what she did to him. She devastated him by leaving him and in his mind, killing his child. He was the fictional characters, she was the bad guys. Still trying to work out where the cop fits in....was the cop his courage? The final scene was him hurting her as much as she hurt him. Thinking he wanted her back and he didn't turn up. His revenge....his closure so to speak. The ladies at the beginning will haunt me forever Tom Ford did an awesome job with his directing debut.
She does say to her friend at the party she didn't understand why Edward never remarried so when he rolled up with Isla Fisher's character, who is a bit of an Amy Adams look alike, same coloured hair as was their daughter India. I figured it was the book. The revenge bits and pieces, the dead animal with arrows in it, the painting on the wall showing a man shooting another man, the painting saying revenge. I think the end where he accidentally shoots himself meant that he is dead to her and vice versa.