What does my dream mean if I'm talking to someone whose died?

Alright, In my dream I was in history cl and we were watching this movie about this Ancient Roman soldier boy who has to live in the town square and the city and has a big pet dog, and they have to survive and I know they had to kill a cheetah. But then, all of a sudden, my Great-Grandma, who I use to live with, and loved a lot, and who had died a few months back, walks in. I knew she had died, but I'm not sure if in the dream she was a ghost or not, but I was like, "What's happening!? Meme! Why are you here!" And she brought me out of cl and I saw a bunch of kids i know sitting at desks and one of my friends had a really outrageous hairdo, and then Meme talked to me and hugged me and said she loved me and told me a bunch of stuff, and some things I don't remember. Then left and I woke up. Can anyone decipher?