I also suffer the blunted affect (blunted emotions) of ME/CFS. Out of all the supplements and drugs (listed in this post) that I noticed increase emotional responses, allicin is the only one that seems to consistently and reliably ramp up emotions, making me feel more human again. Unfortunately the allicin dose required to increase emotional responses I find is quite high: around 6 x 180 mg allicin capsules taken once daily. This then becomes a little expensive, since 90 x 180 mg of allicin costs around £16. I am not sure why allicin boosts emotional responses, but it may relate to the fact that sulphur-containing compounds from garlic such as allicin are known to act on the hypothalamus, and the hypothalamus plays an important role in emotional processing in the brain (and as we know, the hypothalamus may not be functioning properly in ME/CFS, due to the HPA-axis dysfunction, which might explain the blunted emotions of ME/CFS in the first place).