>>20816869She's madly in love
And she's going to leave because she knows if she doesn't at that time, she never will be able to
And she wants him to achieve his dream
inb4 she leaves when he's asleep, and does a Orhime-tier "in every lifetime, no matter how many times I'm reborn, I would always love you" break. I don't think I could handle it.
If they really want to twist the knife, play some really sad music, like the Espurr episode's music.