3 years of obsessing over manually needing to take an in-breath, and I have serious doubts Ash, L-Theanine, or Valerian root will do anything.
I'm a fan of ASH if you are overtraining, or a little overstressed-- good stuff.
L-Theanine is good for in combo with caffeine to cut a little edginess.
Valerian root is also pretty mild, and there are a few studies showing elevated liver enzymes with long term use.
I just think the problem described here is beyond adaptogens, then again there's always the placebo effect-- which does work!
For example, I can't think of any serious case of insomnia that was "cured" long-term with Valerian root or L-Theanine, and if there is an example-- amazing! Furthermore, fantastic!
But for example, in my own attempts to deal with anxiety/insomnia, running through the usual series of herbal remedies just took months and months as well as a significant investment.
One of the reasons I believe the poster should continue to seek medical help is if he were to describe his symptoms to a neurologist, I believe at the very least, he would be prescribed a mild sedative.
Would that be the answer? I have no idea. But most likely it would have more of an effect than Valerian root, and would speed his path towards the correct cure in his case.
Again, I have had periods of similar obsessive thinking, so I'm just offering my opinion in light of my own empathy for suffering through this condition for 3 years.