In the end, it was she who owed him.
If it hadn't been for him, how could she have survived until now.
In just a few words, the relationship between him and her can be summed up.
He was killed and she helped. She was injured and he saved her.
This script is downright cheesy, if it were a script at all.
She suffered a serious heart attack in order to save him.
In order to save her, he gave her his heart.