She knows that he has to leave, and in fact she wants him to. He has to go so he can look after her children, so he can protect them when she cannot. There is nothing that would make her keep him from that, and she would be the first to send him away to continue that task. But he's already promised that this wouldn't be his only visit, and to that is what she holds.

"I don't need you to stay," she assures him gently, leaning just the tiniest bit closer to him. "I just need you to come back to me." If she has the promise of something, someone out there, then she can face this life alone.