Mayella~Is she the coward?

While reading, I started to think about the whole Tom Robinson case and the victim Mayella. I think her story of Tom sounds a little fishy. I just don't think that Tom would have bruised the right side of her face with his left hand. The reason I don't think this could happen very easily is because when Tom was a little boy, he messed up his hand in a cotton gin, and now it is pretty much useless. It would be quite hard for him to do that to her. In the trial, she cannot answer any of the questions that Atticus throws out at her. These questions were along the lines of why she wouldn't have put up a better fight and screamed louder or made a bigger effort to make noise, and why if there were so many children living in that house, why they wouldn't have came down immediately to see what was wrong, and how Tom Robinson could have managed such a crime? She just began crying and yells that the courtroom would have to be a bunch of cowards not to convict Tom. It sounds to me like she is the coward, and she is making this story up? I don't know why or who she would be making up this story for, but it just doesn't sound right to me. Do you think that Mayella is making up the whole story, or do you feel she is sincere and honest about the whole thing? Tell me what you think!