Grandpa

Everything went to hell when my grandma died of brain cancer. My grandpa started drinking...a lot. And he didn't realize it at all.
The saddest moments of my childhood were those when he gets drunk so much that he attacks me and my parents with a knife. We were close, I loved him. But we both seemed to slowly forget that when he started drinking. There were times when he was like before. I was the happiest kid in the world then. But me, my mom and dad had to lock ourselves in one of the rooms and beg he wouldn't break the door. I was between 5, 6 years old so I didn't quite understand why he was like that. In fact I had no clue about madness and insanity, or grief. I simply thought that he was mad at me/us for something. That's when I started hating him. At some point I just wished for him to die and leave us in peace. Just wanted it to stop... A person I used to love so much, a family member, became a monster in my eyes.
I switched rooms some time ago. There is nothing wrong with it. The only thing about it is that it's one of the rooms he tried to get to to stab us the most. Each time I look at the door or the corner of the room, everything comes back. I need to sleep so that I can't see the door, or I start panicking and can't fall asleep for the life of me, for I have a feeling that he's going to come in, even though I was at his burial.