Mindfulness is the willingness to rest in that natural state of awareness, resisting the temptation to judge whatever emotion comes up, and therefore neither opposing or getting carried away with a feeling. Meditation is simply the exercise that is going to give you the best conditions to practise being mindful of these emotions. And headspace is the result of applying this approach. Headspace does not mean being free from emotions, but rather existing in a place where you are at ease with whatever emotion is present.