Huh? Friends? Since when? I don't see Zero drinking a couple of rounds with Tamaki during happy hour, do you?
Your argument loses weight in that he didn't really treat any of his subordinates differently then any other commander would have. And he certainly didn't trust them with his identity, so why reveal more clues by sending them off to search for Nunnally? Especially in a Geass related situation which they would obviously be unable to handle?
I think I already addressed all your points about how he treats the people close to him, and how that makes him more human. You not really countering me here.