It's so hard to do our own dogs because we KNOW what that "special" look is and oftentimes it's nearly impossible to translate to paper. Kind of like taking a photo of a spectacular sunset and feeling that it just lacks "something". It's an exact picture, but something was lost in the rendering. Good luck and my only advice is to actually work on something else for awhile. The more frustrated you get, the less you're going to like anything you draw right now. Go work on something that doesn't even remotely resemble Auggie for awhile and see if that makes a difference.