Dear Welcome to HCM We understand your concerns I went through your details. I suggest you not to worry much. From the given symptoms, I am tempted to say that she is schizophrenic. But the symptoms you are mentioning here could be just your perception. Most probably, as you have limited knowledge, you could be exaggerating. Talk to her and find what he is doing inside her room. Talk to her parents. If need be please take her to a counselor and then to a psychiatrist. Thorough analysis needs to be performed before diagnosing. If you require more of my help in this aspect, Please post a direct question to me in this website. Make sure that you include every minute details possible. I shall prescribe the needed psychotherapy techniques which should help you cure your condition further. Hope this answers your query. Available for further clarifications. Good luck.