What does Katniss mean when she says that she kissed Peeta’s head for herself rather than for the audience?

What does Katniss mean when she says that she kissed Peeta’s head for herself rather than for the audience? She states outright, though, that the kiss she plants on Peeta’s forehead is for her and not for the audience. She has taken control of her emotions in this instance and acted upon them truthfully. Her gratitude for the boy beside her is not an act, and she owns up to that.

She states outright, though, that the kiss she plants on Peeta’s forehead is for her and not for the audience. She has taken control of her emotions in this instance and acted upon them truthfully. Her gratitude for the boy beside her is not an act, and she owns up to that.