What is the question exactly ?
She initially admits that she doesn't feel much toward Thanksgiving, but then progresses to reflecting on the unique memories from her childhood that stick out; she realizes that her perception of tradition was surrounded by a desire to explore and see more variation in the world, experience the new. As she grows older she sees the blatant consumerism and the beauty of 'togetherness' marred by expectations of spending lots of money. As she spends more time with friends and others, they begin to see differently how Thanksgiving can be viewed from multiple perspectives; as she then marries to a husband with a larger family, more diverse, she sees the dichotomy of willing to be in a group of people but also alone. Through reflection she realizes that she actually yearns for the solitude that her childhood Thanksgiving's brought her, and the quiet time with family.
Atticus explains to Scout that a mob is always made up of people. He is trying to explain that, although mobs appear to be a large group, perhaps even an intimidating group, they are made up of individuals who can make individual choices to change their actions. This is a message that Atticus has been sending to Scout throughout the book at various points. Every individual has the right to make his or her own choices.
In this particular mob, Mr. Cunningham made an individual choice not to continue to threaten Atticus. His choice influenced the choices of the other men in the group. This is a powerful moment because Mr. Cunningham made this choice based on Scout's innocent actions to begin conversing with him about his son, Walter. As a result, his opinion changed, and he then changed the opinions of the other men. It was a mob no more. Any small action can change the tide of a mob, either positively or negatively.
