Is there a cure for nightmares?

Last night, I had the worst nightmare I've had since I can remember. I was so scared, that I woke up in terror and went downstairs and sat with my partner for a bit to "cool" off (I always go to bed much earlier than he does, so thankfully, he was still awake). I didn't want to share what happened in the nightmare, but let's just say it was about demon trying to possess me. It was terrifying. It got me thinking, I wish there was a cure or something to prevent nightmares from happening. Before bed, I always try to visualize and think of positive things, and things that make me happy. I think last night though, I fucked up. I knew I had a call the next morning with my oncologist, so I'm sure there was some anxiety going on there. Maybe I knew something bad would happen. Maybe I sensed something negative was going to take place. After the demon dream, I went back to sleep with no problems (and the nightmare didn't continue, thank god). Today, I got the call that I been expecting. It wasn't my oncologist who called, but a colleague of his (that I've met with before). I'm pretty sure she didn't read any of the notes prior to this call. She didn't know that I was off the chemo pills...ok??...that happened in January? She told me that the next step is the MRI (which we knew), and then after that, we would do....surgery. This is news to me. From what I was told, we were doing the extra radiation to avoid surgery and get a complete response (no more tumor). I told the doctor this. She basically told me that a complete response was unlikely, and that not many people get a complete response. WHAT THE FUCK. What are you talking about? Did you not talk to anyone or read the notes prior to this call so that you can get on the same page when communicating something like this? I was told that we are hoping for a complete response! That's what I'm going with. This is what I'm choosing to believe, and this is what's going to keep me going. I think the demon nightmare makes sense now, but I'm not letting this fucked up call ruin my hopes and my positivity. Kiss my ass lady.