"You'd do what you had to do to survive," Clarke said. She may not have known Joey very long, but she knew that the other girl managed to make it outside of camp for a decent amount of time. She had to be strong to do that. "Just like you did outside the fence."
She didn't consider herself brave at all. The things she had done were the acts of a coward. She stabbed Finn because she couldn't stand to watch him suffer and she irradiated the Mountain after making the mistake of trusting Lexa.