I took Benedryl for YEARS for sleep. It was recommended by my doc and since I too have Fibro and pain is increased by lack of sleep and in fact, has been induced in healthy volunteers by lack of sleep, I took it and it worked like a charm. I did take it every night, but I can't say I felt "addicted" to it, it's not like it's a narcotic.
I am now taking Melatonin, again by doc's recommendation, sleep with a CPAP mask (and if ya wanta see sexy, see a CPAP mask with the hose hanging off ya) and also take Soma, an older muscle relaxant which helps with the pain and sleep.
I have also used the notepad routine to avoid my mind running in circles. Before I had to quit work, it used to keep me up for hours, it was like a bunch or mice up there running on a wheel. Once I got it on paper, tho I could let it go. ;)