I have exactly the opposite idea of what mindfulness is -- at least what is effective for me. That is, to be aware of whatever is in my mind, and not censor it or shut it off. I have a major tendency to deny feelings of fear, for instance -- I think that is because in our family the expression of fear was intolerable to my mother, who would then punish us or ridicule us for expressing it, thus causing more fear. Being able to admit to the "bad" feeling is liberating (in spite of the fact that it can be still fearsome).

No it's not numbing, but opening to a different feeling - distinct from emotion.