I am so sorry to hear what you went through. What you say about disconnecting from reality makes perfect sense - the brain tries to protect us in any way possible, and dissociating like that is a big coping mechanism.
Your hatred for your abusers is completely valid and understandable. Is there any way you can limit the amount of times you see them, or just set a boundary that you never see them? Would either of those be possible?
You mention that no one, especially your mom, knows about the abuse. Do you think it would b helpful if someone knew, and if your mom knew? It's a very painful secret to carry around with you all on your own. Or maybe a doctor, counselor, or therapist?