Justice in Identical

In the book Identical by Ellen Hopkins, which I just read, I don't feel like justice is served for much of the book. In the end justice starts to be served. In the book there are two twins and one is sexually abused by their father. The twin that is abused doesn't tell anyone about it and just lets it continue. I believe that justice is served at the end of the book when the father is punished for his actions and the daughter doesn't have to deal with him anymore. It's unfair that she had to keep all of that inside her for so long maybe not fully aware of how horrible it was. She has this huge weight on her with all the stress of her life and at the end the weight is slowly lifted. I think that's when justice is served in the book. But I'm also not sure if justice is ever really served. I mean the girl had to go through all this unfair stuff forced on her by her own father. If that happened to me I don't know if I could ever feel like justice could be served. Too much injustice would have already occurred and hurt me. I think at least a little bit of justice has been served by the end of the book. But is it enough to really make a difference?