I do have to repeat this, feeding raw has nothing to do with aggression. Bad genes and bad owners cause aggression, either through poor training or LACK of training and structure.
Dogs are not little humans and you need to stop treating your dog as such. Hugs are generally perceived by dogs as acts of threat not affection. It sounds like the breeder's concerns might be in the right place when she is blaming you for not raising him appropriately. What baffles me however is how an inexperienced person like yourself ended up with a working line dog, that's a big no no. And no, having a GSD prior does not automatically make you experienced, the type of knowledge you have obtained from the experience does and you sound like not only a very inexperienced dog owner but one with some very incorrect ideas about dogs.
You need to hire a trainer who can work with you to put you on the right path of how to raise, train, and treat this dog properly because this is a disaster waiting to happen if at 6 months he already feels it is acceptable to attack you over his food.
In response to your breeder saying you have not kept up with the training you said but you walk him 2h per day and he has a pool. That is not training. That is exercise. And mindless play and exercise are completely different then training or purposeful exercise which supports your training.
It is also not too young for a pup to leave at 7.5 wks of age. Working and police dogs some times are allowed to leave even earlier then that as they go into training and appropriate socialization and environmental exposure right away and this is work that is best done at this age. Most pet dogs go to new homes at 8wks of age. You can't blame your dog leaving the breeder 3 days before that as the reason for the issues you are having.
My suggestion, if you live close enough to your breeder ask her for help. She knows the lines of the dog, I'm assuming she trains police dogs? That would make her very qualified to help you. In cases like yours, it's not the dog generally that needs to learn and change, it's more of a case of the owner learning how to appropriately raise their dog and how to train them. You can also ask your breeder for referrals for trainers if for any reason she is too far for you to travel to.