Since it really isn't a new issue I will ask you the following:
Do you eat a lot of carbohydrates? If so they are natural sugar and you may need to cut back on potatoes, carrots, peas, rice, corn, noodles etc as well.
Secondly she may just not require as much sleep as you do, it happens. I used to do very well on just 4 hours a night and "no" I did not nap during the day either. It may just be her metabolism. Albert Einstien only slept in snatches of 10 to 20 minutes at a time 5 or 6 times a day and he was fine.
Is she getting enough exercise? Have her outside in the fresh air more, walking, bike riding, swinging, etc. Fresh air does seem to help a lot. If available swimming is really great.
Keep her active, exercise is a great way to wear you out enough to rest better.
Monitor what she is reading and definitely what is being watched on television. After say 6:30 p.m. no heavy action shows and nothing thrilling or scary. Have her read more in the later evening and have it be something like "Little Women", Nancy Drew mysterys are pretty tame, "Tale of a Fifth Grade Nothing" or the Little House on the Prarie Series. She can read these while in her bed.
A cup of warm tea, hot cocoa (not hot chocolate) there are some like tension tamer and sleep well teas that help relax a person as well. A nice cup at bedtime with a book helps a lot.
Does she have a radio in her room or a CD Player? If so I noticed with my children that playing music softly helped them relax and finally sleep as well. Naturally it has to be monitored music, I don't suggest rap or heavy metal. Maybe Creed, Celtic Music, Native American Flute Music, and some of the new age stuff the massage therapists use is good for helping you relax as is ocean sounds, wind sounds, etc.
Good luck you have my sympathy and my prayers.