"You're not making any sense, Amelia. When I found you you were begging for me to recognize you and now you want to be left alone? Wasn't that your nightmare? Being forgotten and alone? Why are you doing that to yourself now?"

Steve doesn't raise his voice. He's worried about her but knows that getting into a fight or an argument will end badly for the both of them. Steve doesn't want to hurt her. He just wishes she wasn't quite so good at hurting herself.