You've wept for him to come back to you. You never meant to "abandon" him. But it just wasn't safe. You needed to save him, erase his memory. Make sure he wouldn't come back. She didn't think you could protect her. But she could protect you. You "casted" him away.... Now he's here. Here to try to learn why he was sent away. He's cold now. Now her could protect you. Just maybe...

"Why... Why did you cast me away! We would laugh, play, pick flowers! I even called you mother from time to time! Why! Why did you make me go trhough hell down in Teyvat!"