Liz, my heart goes out to you. I think your body is telling you it just can't take all the stress. It is screaming. Even though mentally and emotionally you may have it under control, your body is saying no. It can take a very long time to heal from such emotional trauma so be patient. You may experience one illness after another for awhile. And you may never be the same, ever. I don't say that to frighten you. It can actually be a good thing when our bodies force us to slow down, re-evaluate and cast away the trivial timewasters.
I can't emphasize enough wholesome nutrition and routine, routine, routine. Which of course, may not be entirely possible given the recent events. A daily walk--gentle, not beating yourself up on a treadmill in a crowded gym with loud music (although that is probably better than nothing). Pilates, yoga or some other form of meditative exercise. Cut out all caffeine and alcohol.
If possible, schedule a massage once a week for awhile to deepen the relaxation in your muscles. (even an hour long facial works for me--not the make-up kind that Mary Kay offers but a true spa experience where you lie on a warm table in a darkened room--warning, your hair will be a mess so plan on going straight home

) If possible, plan your appointment when you don't have to go somewhere immediately afterwards and ask if you can be scheduled for an extra half-hour just in case you do fall asleep. Ask the massage therapist not to wake you. The goal here is to train your muscles and mind how to relax.
If you have not tried it, at least look into transcendental meditation. I realize it is one more thing to try to fit into your life, but it truly is helpful and has medical studies to back it up. Other forms of meditation can also be helpful. Again, the goal is to train your mind to relax or focus on something non-stressful for 15 to 20 minutes at a time. I like gardens. Looking through beautifully illustrated magazines and books (as long as I am not stressing about how to do it in my own yard) on a regular basis has been helpful to me in the past.
Get some extra help if you can afford it. Once a week cleaning service to keep the main areas of your home presentable (just being in a clean, organized room is soothing). Take one hour a week to clean out a drawer, a closet or a shelf. Just throwing things away is therapeutic for me. It is like throwing away stress and ugliness.
Accupuncture might be helpful if for nothing else, an hour in a quiet, darkened room. Look for someone who has a degree in Oriental Medicine or is otherwise credentialed in your state and ask her/him if s/he has had any experience treating insomnia.
Your medical insurance may pay for accupuncture or massage therapy under certain conditions. It's worth looking into.
To sum up, avoid stressors as much as possible including caffeine, etc. Give your body the tools it needs to handle life's assaults including wholesome foods and gentle exercise. Practice relaxation techniques such as massage and meditation. However, all the healthful things cannot counteract the bad ones if the bad ones are in huge abundance. That is why one needs to eliminate as far as possible the stressors.
Lastly, scripture reading has helped me tremendously. It is one of those daily maintenance things. I usually can't pinpoint one passage or one "ah ha" moment, but rather it is the daily reading that somehow makes my life more manageable. If I skip it for awhile, I find myself less able to handle the day to day things (and we all have them). When I read daily, I can handle things better.
I still have occasional bad nights (nothing like what you describe, however) and it takes me longer to fall asleep than it does DH. Nightly, I am amazed how quickly he falls asleep while my brain is still churning away. Some of that may just be an individual thing and not to worry about. I will keep you in my prayers.