You can see how their relationship becomes the healthiest of them all: 1. Armin does not forgive Annie, but says that he is no better than her. And this is correct, because forgiveness automatically puts one person more important than another. He is not going to correct her, but accepts her as she is. 2. “I want Annie to remain herself” contrast to the conversation in Stohess “If you don’t come with me, you’ll be a bad person.” Armin understands Annie's importance in the final battle, but he doesn't want to force her to go with him. 3. and the last one, which has always been with them: “you are weak, but courageous”, “you are a kind (good) person”, implies seeing each other through, despite all the masks being built.