I lost a very dear and close friend 6 months ago to brain cancer. Her most difficult time was at night when everyone and everything is quiet. She could not stop her mind from thinking of all the sad, bad, and emotional things associated with having terminal cancer.
So, I started reading to her at night. If I was not with her, I would read to her over the phone. If we were together, then I would read to her in bed until she would fall asleep. This became the one thing she absolutely loved, and it really made me feel like I was doing something for her that helped her. It does not matter what you read, that can be discussed between the two of you. It really helped her to be able to drift off to sleep with out going crazy with all the thoughts that would go through her mind at night.
Hope this gives you some ideas.