Dynamo87, firstly, thank you for your service Devil Dog! God Bless you for your sacrifice.
I was USMC Platoon Leaders Class 1988, TBS 1989, and in Iraq for D-Shield and D-Storm about ten years before you. When I got out I was a cop in a large and high crime city for a few years.
As a result, I've had my share of sleep problems over the years. DSIP can be helpful. CBD with terpenes can be very helpful too. Smart move on the VA recommended RX, you will get diminishing returns, have a rebound, and end up on a long frustrating chase across multiple meds.
What I have found to be more helpful than any supplements or drugs, however, are as follows:
Cognitive Behavioral Therapy for Insomnia (CBT-i)- teaches you to quiet your mind and control run away thoughts
Hypnotherapy for Insomnia- make sure it is from a clinical and board certified hypnotherapist and not your average "cease smoking hypno-guru"
Binaural Beats for Sleep- google it. It will sound hokie and weird at first, but the effects that these frequencies have on the mind have been studied extensively by Universities, the DoD and even the Intelligence Community. It is for real. You have to listen with high end stereo head phones though, not earbuds. It will sound like quackery when you first read about it, but a lot of it is available on line for free, so well worth 30 minutes of your time to try it. If it doesn't work, ditch it. Worked for me though.
Feel free to PM me if you like.
Semper Fi