He won't, because you won't be stuck here forever.

[She sounds confident in her assessment, states it as though it's fact. She has to-- she has to believe in it herself, or else otherwise the efforts she and James and the others are going to in order to try and change things are for nothing. She has to believe that they can keep their memories and get out.]

It's only a matter of time. We'll find a way out. Even if he's gone home, you'll see him again.