I'm going to tell my girlfriend to get rid of her rescue dog
Why would you tell her to get rid of the dog?
I want to have dog puppies and I think it's not a good breed for a puppy.
Getting rid of a dog is a collaborative effort. If your girlfriend does not want to give up the dog, then that should be the end of the conversation.
She's not letting this go and she thinks I'm going to care for that mutt as much as her! I'm going to break up with her!
Don't you think you're overreacting a little bit here? You should never be telling your gf to get rid of a pet she loves. That's just cruel.