I think my GSD has a mental defect

Question
My GSD is 1 year and 3 months old. His name is Chopper. I think he may have a mental defect. He is the most georgeous specimin of his breed but he is aggressive towards our other dog and basically everything he does. I have had him since he was 8 weeks old. Even at that age he just about bit my nose off. He runs at a person so fast that he litterally knocks them 3 feet into the air. When we take our dogs for a ride in the truck, he clearly shows that he is the alpha male and he attacks Drako (that is our other dogs name). We had him in obedience classes and they still did no good. I dont know if he is just stubborn but he still after all this time will not give a shake. He loves to play in the waterhose and last week he acctually bit my hand because I was holding the hose. I love Chopper, but he is abusing everyone in my family. If my boyfriend scolds him for doing something bad, Chopper barks at him aggressively. I have never abused Chopper in anyway, but I am firm with him. I am at my wits end with Chopper. I love him but I have been getting terrible headaches just trying to deal with him. Basically, I dont understand why after all this time and training and love that I have given him, why he is so dis-obedient?

Answer
Hi,

Sounds like you have a very dominant dog on your hands.  Chopper needs to know who the leader of the pack is because right now he thinks its him.  So, there is no mental defect, he is quite normal, unfortunately he is a bit out of control.  Because I cannot see him in "action" I would recommend getting him evaluated by a qualified dog trainer, and see what they say.   He is still young enough to change, provided that you are willing enough and patient enough to see it through.  All the time, training and love you have given him does not count in his mind.  You need to firmly and consistently practise some leadership exercises with him, using techniques recommended by a trainer.   

Hope this helps,

Lori