How do I handle a mean person?

I reported a man to law enforcement for abusing his dog. He beat the dog and was proud to tell about it. The dog suffered horrible abuse at this man's hands. The man told me to take the dog, he did not want it. I was so happy. But he is known as a crazy in this small town. He would not give me the dog. I begged for the dog, as I had a great home to place him in. The man refused to give him up and told the police he would kill the dog, before he would let me have it. I believe that is just what he has done. Law enforcement is done with this guy...sad but true. He is in trouble with the law all the time. Has been his whole life. Everyone knows this guy is nuts. The dog is gone and I know he killed it. I have to see this man almost daily. He lives in the same town and he is always at the coffee shop or gas station or wherever. I know he will come up to me and tell me gruesome details of how he killed the dog. I really feel horrible about this, and want to be prepared for a response. I don't want to break down and I want to have a reply that will diffuse this psycho. Any ideas?