Second Year:
He literally saved your life (and several others), Ron did (with Harry's help, as well as Hagrid's, but…). He faced his deepest fears for you, braving the Forbidden Forest and all those spiders, he snuck out, risking detention (and, Merlin forbid we bring up the flying car). And he solved it. He solved it. ("You solved it, you solved it!") He found the Chamber of Secrets, nearly lost his memory, but saved the day.
And he learned trust you. The Polyjuice Potion? He had faith in you, that you would make it correctly, that it would do what you needed to do.
He faced spiders for you.
Now that is saying something.