I'm sorry took so long to respond...I wanted to wait until I had enough time to really read what you wrote and compose what I want to say.
I am sorry the nightmares have been so awful lately. I know that must be so very very hard and tiring for you. I want to tell you that it was NOT your fault that your grandfather abused you. Not at all. You are not a horrible person, and you did not deserve to be hurt. You matter, and your feelings matter, whether or not there are adequate people around to tell you this. I know oftentimes people react to us in whatever way we believe they will, because they can read that in us. For example, if we think we are unlovable, then we don't easily attract love. Unfortunately, we have no control over the fact that we were taught these negative messages about ourselves, even though they aren't true. What we can do now, though, is to actively work on changing these messages/beliefs. I do this by using self-affirmations. For example, if I feel like I am worthless, I tell myself "I am a worthwhile person" and "I matter". It takes time to reprogram these beliefs...it does not happen overnight. But it can be done. I encourage you to work on this, because you deserve to feel good about yourself and to have friends who love you and support you. I'm glad you're here.