In Asian languages, the word for 'mind' and the word for 'heart' are same. So if you're not hearing mindfulness in some deep way as heartfulness, you're not really understanding it. Compassion and kindness towards oneself are intrinsically woven into it. You could think of mindfulness as wise and affectionate attention.

Full Catastrophe Living (Revised Edition) (ed. Bantam, 2013) - ISBN: 9780345539724