When Carlisle realizes that the woman he is treating for a failed suicide is the same one that he treated for a broken leg years ago, he is devastated. The memory of Esme has stayed with him since they first met and now, she lay dying from internal injuries. He doesn't know exactly why, but for some reason, he know he can't bear to lose her. After a one-sided conversation with the comatose woman, Carlisle makes the decision to change her, hoping that she won't despise him afterwards for it.