"I'm fine with it 'cause I've got to be." It's not entirely an ingenuous answer - after all, she's not completely fine with it; seeing her parents, hearing them, hurts. But. At the same time -

"You can go mad from all of it, or you can just deal with it. I've rather too much to do to go mad, so that only leaves one option for me." She offers a sharp shrug, and thrusts out her arm again to wave away the mist that threatens to re-form into his mentor or father or whoever that previous ghost had been. "You're free to turn into a gibbering lunatic if you like, I suppose."