I've been through this many times so I know how it feels. But its usually because its a reflection of my fears. So what I do is accept it as my fears and remind myself that even though the dc seems evil or gives me pain its going to be ok.Than I think about how the character is going to change into a good one or that the pain is going to go away. Than they end up showing their true colors. That they are harmless like little flys that might annoy you but they don't have power over you.

For example, Once I was shot in the head with bullets in a lucid dream because the dc didn't like that i disobeyed him because i said it was just a dream. I didn't like how it felt as my body also broke apart after that but it was because i gave my attention to the feeling of the bullets. Another time a character shot me in the head and i managed to make it go through me like nothing. Just know you can change the outcomes that happen in your dream to a positive one.