Oscar is fixating more on his relationship with his dad and what that meant to him because that's gone. We see a lot of him grasping onto what's gone and what he can't have anymore. I wonder when people are watching this movie if they thought that she was being inappropriate in her fight with him but to me that was very authentic. She's been really patient really been actually like creating a lot of like fear and within an anxiety within herself by letting him go off and do his own thing then when he comes in and is like attacking her kind of you know it makes sense.