"Right? Well. I used to be-- it used to be-- I don't know, it used to not feel so much. Back when it was just fun, gallivanting around-- but then I don't know. Something changed." The Time War mostly-- but even before that.

"Pretty soon the weight of the universe really bears down on you and you get really tired of saving it every five seconds. But I've moved past that." More or less. Or at least she had a better handle on how to deal with that kind of depression.

"Live long enough and you'll learn it I suppose."