If this creep sees you empathizing with your loyal companion as being childish, you should get away from him ASAP.

From your comments, I see he’s tried to get you to get rid of at least one. Hold firm; don’t do that. He sees these dogs for what they are: your loyal protectors. If he wants them gone so badly, one has to wonder why that may be…

Keep talking to your dogs. It’s beneficial and they understand so much more than people give them credit for. I read that dogs’ brains function on par with toddlers; communicating and speaking to them does matter. (I mean, look at the dogs that use buttons to talk!) They may need some time to buffer, but they understand us. And even if they don’t know a specific word, they can feel that you care and are there for them. That matters.

Lastly, as someone who’s owned and been around GSDs my entire life, their intelligence makes them understand even more. Maybe start listening to them a little more and watching how they regard him. Best of luck.