My mother did alot of bad things to me ( i am with a step mother now but they are more like parent then my real birth parents) anyways i havent remembered it until ive been remembering it in my sleep and the fear of it all and the trauma.
Sometimes you can suppress certain memories so much that out of fear, your mind blocks it so you don't remember it anymore. Then it can happen that something triggers it and brings back that suppressed memory. You've been remembering it in your sleep because your subconscious still remembers it. You can try to talk with someone and let it all out. You'll probably always remember it, but within time you can give it a place and move on a bit better. You could try to talk with your stepmother about it or a counselor from your school. You could also try to see a therapist who can help you through this. This doesn't have to haunt you forever. If you want to talk about it, you can always message me.