Perhaps you need a philadelphia collar for starters to help avoid spinal cord insults by your rogue disks (and instability), also it will help hold your head in good relationship with your neck, to help the flow of cerebrospinal fluid. Certainly wear it whilst carrying out tasks that involve a lot of head or neck movement.
Secondly make sure you are getting enough SALT, since the ‘low-salt’ nonsense that many people have taken on board is definately multiplying our problems. Salt is an essential nutrient, needed for correct neurotransmission and proper digestion of food. I’ve certainly felt a lot better this year by ensuring I get at least 2-3 grams of salt every single day. I’m now off the Zantac totally and I never have any stomach problems. Many of our problems are caused by poor digestion and and what if much of our pain was caused by malfunctioning neurotransmitters ?
Thirdly, Make sure you get protein and vitamin C each and every single day, to help your body produce enough quality collagen to carry out any repairs because your body is in great need of help, at the moment. A multivitamin with added minerals would help too. I’d take Epsom Salt baths (or footbaths) to replenish the magnesium that your drug regime may have depleted, this should make you feel a bit better too. Have you seen the info on Magnesium on this site ?
Have you had a head MRI, if so, what were the results ?