It's not an easy thing to face. Even knowing that she'll come back, it takes very nearly all she has to not recoil at the option, not ask if there's someone else who could have done it instead. Some stranger as opposed to having it need to be this.

"Thank you," she manages, after a long silence. It still hurts, and in more ways than just the physical, but it's what needs to be done. Anything else that happens afterwards is presumably something that can be dealt with. In any case, coming back is better than going on like she is, and she simply waits for Cuthbert to finish, as she tries to hold herself together for these last few moments.