In the novel Speak, what are things that change in Melinda Sordino?

When the novel begins, Melinda is a broken person. The rape has scared and scarred her a great deal. Additionally, nobody knows about it; therefore, everybody just assumes that Melinda ruined the party for no good reason. As a consequence, she is completely ostracized from most of the student body. She has completely turned inward and even physically hurts herself as a way of dealing with her inner pain.
As the school year progresses, Melinda begins to gain more confidence in herself and in her ability to speak out. It's a slow process, but things like watching daytime talk shows actually provide her help. For example, Melinda does wrestle with knowing exactly whether or not she was indeed officially raped, and it is Oprah's show that helps Melinda to correctly identify that she was indeed raped.
I would say the other main contribution to Melinda finding the courage to speak is her former friend Rachel. Rachel has tried to distance herself from Melinda, but Melinda continues to care for Rachel. When Rachel begins dating Andy, Melinda knows that her friend is in danger, and that helps Melinda find the courage to speak out.