I have an 18 week old german shepherd, greyhound cross & I am really struggling on crate training him and also teaching him how to be left alone. I can't even go into another room without him screaming the house down. I understand that I need to get this under control soon as I know that it can lead to worse problems further on in life & separation anxiety. I understand that it can take time but any help would be brilliant. He hasn't been left alone at all due to all of this & at some point I'm going to have to leave the house!