Can appreciate the "overactive mind" part. I tend to wake up thinking about what needs to be done the next day, or fretting over business problems. This is what I have done. Works very well for me, and I pass it along for your information and thought.
1. The primary, best thing I did was to KEEP MYSELF FROM CHECKING THE TIME WHEN/IF I WAKE UP. We have a clock in our bedroom (I need it for the alarm), but if I wake up, I do not look at it. Checking the time gets the brain engaged, and starts the thought process. I mean this. Absolutely no time checks. I roll over and just go back to sleep.
2. The usual: room dark, nothing too active mentally just before bed (I have reading I call "bedtime books" which are fun, engaging, but not strenuous), room neither too hot or cold. I like a rain on the cool side, and prefer fresh air (even mid-winter ... this makes for some spectacular fights with my wife ;-) White noise (perhaps an electric or ceiling fan?) can be helpful for some folks.
3. Perhaps the hardest: I schedule bedtime and waketime. 7 days a week. I usually go to bed around midnight, and wake up around 6. On weekends, I may let myself sleep in 'til 7 or so, but not much later.
4. If mental activity is a problem, your friend may benefit from a peaceful mental scenario. The example I give is this: I can make myself go to sleep quickly, even when rattled, if I envision myself on a long (preferably trans-continental) plane flight. Peaceful? Yep: no phone calls, no pagers, I can just relax, watch a movie, and read. (This scenario was a little less than successful last September and October, as you might well imagine ... )
5. Finally, in the "none of my business" category, I would suggest trying to go without the sleep meds. As your friend has found, they are often not helpful, and I suspect actually interfere with the body's sleep patterns. I used Melatonin for a while, and found it helpful then. I don't use it now, and readily agree that there might be a placebo effect going on.
Good luck to your friend. Lack of sleep is tough. I wish him the best.
Jim Huffman, RN