I dreamed that I was possessed by a ghost this morning, and then a mage helped me drive away the ghost. Then I started to go crazy like a demon possessed me. ...

Never mind, dreams are all hype. Don't you find that the scene you described is very similar to the usual horror movies? Therefore, it is possible that the horror movies you usually watch affect some thoughts in your brain when you are asleep. If you must follow Freud's dream interpretation, I think you should first consider that you have some anxiety about real life. And hope to be redeemed in some way. The scene where you are controlled by ghosts is just a state of mind, reflecting your contradictory attitude towards things. That is, everyone has two sides. On the one hand, things are easy to think of evil, but at the same time, there is a good side in your heart. I suggest you relax. Usually watch more comedy movies to adjust your mood. Good for both body and mind.