Also, there may be external things that may be keeping you awake (like subtle sounds and lights that you may not realize are there, but are bothering you). Try wearing a face mask over the eyes and ear plugs.
Most face masks I've come across aren't comfortable and let in too much light at the cheekbones or by the nose. The most comfortable I've come across that does keep out the light are the ones put out by Tempurpedic. I get way too much light in the bedroom when I try to sleep from the streetlights glowing through the windows, to the little glowing light on the TV (I guess it's on for the remote to work), to the little blinking lights on the modem router, to the light on the computer printer even when it's on standby. When I first fall asleep, those lights don't seem so bright or bothersome, but once I've gotten drowsy, or have fallen asleep but might waken, they sure seem bright! Only problem with a face mask is that sometimes it'll slip off, or I may wind up taking it off because of it making the face too warm later in the night.
As for earplugs, find ones that are comfortable to you. I've tried many, and most I don't find very comfortable. But I've found some purple ones at Wal-Mart (I can't recall the brand) in the pharmacy area where the ear products are that I do find comfortable. And these block out the most decibles as compared to all the other earplugs I found there ... and I even compared them to what was over in the sporting goods department for gun users, these were better! The earplugs do NOT block out all sound, just muffles things enough (like a spouse's snoringógotta love 'em, just don't love the earth-rattling volume when trying to sleep!) so that you're not distracted and can sleep yourself. So you will be able to hear if there's an emergency.
I'm super sensitive to the miniscule sounds and lights that most people don't notice during the night. These absolutely help me to fall asleep, and stay asleep better.
The face mask and earplugs could help you to trick your mind into thinking it's a little later in the night, so you may be able to fall asleep earlier.
Also, try some of the brainwave entrainment CDs for sleep, like the Jeffrey Thomas ones.
I also highly recommend Dr. Jon Kabat-Zinn's meditation CDs, especially the guided mindfulness and body scan. I almost always fall asleep before finishing a full body scan. Not good for the meditation itself, but for me I'm thrilled at the falling asleep. The meditation would help you with the adrenal problems, too. I like his meditation methods better than others I've come across; they've been more effective for me. While with other meditation methods you actively have to focus on breathing and thoughts, this method has a nicely passive approach, more just recognizing you are breathing (no set way you MUST breathe) and if a thought pops into your head recognizing you had the thought but just letting it drift away instead of concentrating on it. I think this is particularly good for when you try to go to sleep because I think that's the problem insomniacs have ... they latch on to a thought or thoughts and worry over them such that they aren't able to let their brain go and relax into sleep. Your brain knows what it needs to be doing for the body, but we often don't allow it do do its thing. This method of meditation allows the brain to do what it needs to without our conscious thoughts sabotaging the brain's maintenance of the body and mind.