>>13342281This doesn't help many people, but for me meditation did it. You need to keep at it, though. Meditation is hard especially for people who can't stop thinking.
I learned to divert my attention from my thoughts and external stimuli to their absence (of which there is always some level; you are never fully active).
However, it's not perfect. I still get some fits where I can't stop thinking, organizing etc.. But my control has gotten much better over the years and sleeping is not a problem anymore. However, without reducing workload and getting some balance in your life you won't get far.
I recommend Vipassana meditation because it has no religious assumptions (only listen to external stimuli or other stuff). The method by Shinzen Young is relatively straightforward, but ignore his claims that he does a scientific form of meditation (it's just regular meditation without any religious hoopla).