The fact that Rick had this look on his face when he saw Carol:
He didn’t know about Judith. He wasn’t completely sure if she was the one who saved them. Just seeing her was enough.
Bonus: Maggie’s thrilled smile. That makes three people who knew about Karen and David the ones who were actually the happiest to reunite with Carol.
He never, never stopped caring about her. And I think it shows in spades.