My fiance's dog (silky terrier) is very possessive and has a lot of anxiety. He got hit by a car about 2 years ago and it has gotten a lot worse ever since then. The biggest issue with him is when he has a treat or human food in his mouth (whenever he grabs something off of a table). If you touch him or even go near him he will begin to growl and show his teeth. He can do the drop it and take it with his toys but with treats he is a completely different dog. I just recently got him a chew bone too keep him busy when we are both out of the apartment. He doesn't chew on it when I give it to him but he will just keep it near him. If i make any noise or even get up to do soemthing else, he will dart torwards the bone and protect it by growling. What are some good ways to get him to stop this behavior?