Welcome to psychcentral natani girl and thank you providing all your history. In order to get an evaluation I think you need to see a personal psychologist or psychiatrist but the 1st would be better, so you need to ask one of your parents to set up an appointment. I'm so sorry you're were abused by your grandfather and have a dysfunctional family. To answer your question - yes all your past family history as well as there being some existing family history of mental illness...all this would account for how you're feeling. I'm not surprised you would be affected by all that's happened to you and witnessing the stress in your house.

I think at the right time you need to tell an adult and your mom about being abused by your grandfather. He could be abusing other kids in your family or extended family and he needs to be stopped. By telling, this will stop further abuse to others. When a child sees their parents all stressed out, they often absorb it and think its all their fault but its not. I think you need more than a school counselor. I pray you get the help you so deserve.