Grandma Wandering The House

Before my grandma died she went a little bit... Well... Mental. She couldn't do anything by herself. She would always wake up in the middle of the night and wander up and down the hall, shuffling her feet as she went. Countless time we had to take her back to her bedroom, because she couldn't remember why she was up. She died when I was 11. At this age I was up until very late every night, playing on the computer until at least 4am. On several occasions the same thing happened:

It would be around the 3-4am mark, and all of a sudden I would hear shuffling coming up the hallway from my grandma's old room. I would be so terrified, I didn't dare move. The shuffling would get louder and louder and all of a sudden stop right outside the computer room door. Then silence. I would be so petrified I wouldn't even leave the computer room if I hadn't heard a noise for ages. This happened on several occasions and eventually I didn't dare stay up so late because I couldn't bear hearing those noises. But sometimes I would still randomly wake up during the night, and hear creaking in the hall, and shuffling.

One time, during the middle of the day I even saw a flicker of a shadow passing between two rooms. A woman dressed in a white gown. It was gone in a flash.

Do you think it was my grandma? If so, was she on some kind of loop? I have since moved out of that house. I have never felt as though this "presence" was comforting in any way. Simply... Wandering.