It was just a combination of things you said that made it sound like you were against holistic medicine.
Anyway, let's start with myelin. The majority of myelin is composed of lecithin, and supplementing with lecithin granules will help increase myelin production. I recommend 1 tablespoon three times daily with meals. Larger doses are not recommended due to the high phosphorus content, which can have adverse effects on the bone. The fatty acids EPA and DHA as well as sublingual B12 in the form of methylcobalamin or trimethylglycine (TMG) also aid in the regeneration of myelin.
It will take some time. Myelin regenerates so slowly that it was once thought it did not regenerate at all, but we now know it does.
To help slow down brain over firing I recommend amino acids that increase GABA levels in the brain. The best are glycine, glutamine or taurine. Amino acids are best taken on an empty stomach at least 30 minutes before meals since they compete for absorption.