If you can get sky 3 then watch the dog whisper with ceaser millan he is fantastic. It sounds like your dog believes he is pack leader and needs to protect you, dogs do not understand our world and need to be at the bottom of the pack in order to be happy. you need to eat before your dog without interruption, you need to lead the walk, as the leader of the pack is the hunter and the strong one and be the one they follow! When you leave your house and your dog chews things its because they r worried about you, as they believe it is their job to look after you and they cant as you are not there, thats why when you get in and they bound at you, you must ignore them, say hello to other members of the family, wait until your dog is calm and then call them over to say hello to them! Do all these things together and things should slowly change for the better! Hope that helps you.