i would try meditation i have trazadone, prazosin that aid my sleep can you take meds?
I do imagine that you are scared and have nasty nightmares...Have you talked to your surgeon about this?? He/She needs to be kept informed of your progress....
There is much relaxing music on YouTube, some of it is labeled as Meditation Music but is very soothing and you might try there.
There are also Binaural Beats that are recorded at different frequencies, some for healing, some for soothing, some for meditation. I have much fun at YouTube just listening that soon I am actually less stressed...
Good luck with your surgery and your recovery....I would love to know how you are doing
M