I want to add that like others pointed out above, mindfulness is not meant to be blocking things out of awareness -- more the opposite. It's more a peaceful observation and acceptance of thoughts and feelings, and their endless dynamic. I find it especially helpful during very emotional times. My old habitual way of dealing with many emotions was exactly blocking them out and detaching. For me, a mindful existence is more a state of high awareness, non-attachment, and equanimity. Being able to view and attend to our our thoughts and feelings without being swept away by them or acting out impulsively.