Haruki hears about Kazusa's moving from her mother, who she hadn't been on good terms with.  He feels betrayed and angrily confronts her.  But his words force open the door to Kazusa's heart, which she had desperately tried to keep closed so that the three of them could stay together.
Don't force yourself.
Überanstrenge dich nicht.
No hace falta.
No hace falta.
Ne force pas trop.
Não se force a vir.