Quote 16
Maybe it's because I still have the ashes of my own district on my shoes, but for the first time, I give the people of 13 something I have withheld from them: credit. For staying alive against all odds. (2.82)
Katniss realizes here that she hasn't given "credit" to the folks in 13 who have been struggling for their lives just as she has been struggling for hers. In some ways, they had as tough a time making it in 13 as she did in the arena, and she hasn't given them enough respect for that.
Quote 17
"That's great," I say. Prim a doctor. She couldn't even dream of it in 12. Something small and quiet, like a match being struck, lights up the gloom inside me. This is the sort of future a rebellion could bring. (10.72)
Here, Katniss is able to recognize one of the things they're fighting for – the rebels, and thus a new and brighter "future." It's just a "small" feeling of courage inside her, but it's a chance for hope, for possibility. As terrible as the events they've gone through are, there might be something better on the other side after all.
Quote 18
"Anyway, it's not like an actual Games. Any number of people will survive. We're just overreacting because – well, you know why. You still want to go, don't you?"
"Of course. I want to destroy Snow as much as you do," he says.
"It won't be like the others," I say firmly, trying to convince myself as well. Then the real beauty of the situation dawns on me. "This time Snow will be a player, too." (18.26-28)
It takes a special kind of courage to enter into a version of the Games for a third time. Most folks are too terrified to even make it through one. Katniss and Finnick have already had to endure two, and it's a miracle they both made it through those alive. Here, it's hard to know whether Katniss is really "convinced" by her rhetoric or not. More people might survive, but more people will probably die, too.