Cody really didn't expect to like Noah as much as he does. He also didn't expect Noah to make him this happy. That's why it hurts when he realizes Noah's better off without him. Without his baggage, without his adversity, without his mess. Man what a mess it is. He wouldn't blame Noah in the least if he thought it was too much to handle and left without looking back.
Fortunately, Cody matters too much to Noah to let him go so easily. Cody couldn't be more grateful. Maybe one day he'll learn to tell him.