It is not necessary to react to everything you notice.
This is just another way of saying ‘pick your battles’ but I don’t think we can ever hear this particular form of wisdom in too many ways.
Life is full of reasons to react. Every single day, life offers a boat load of injustices to all of us. We can react to all of them, but we can often effect actual change in few of them.
Pay attention to the things life shows you, but most of all, pay attention to yourself. Invest your reactions only in the places that really matter – be wise with your energy and who and what you spend it on.
If you make it a practice to budget your reactions you will never have to worry about ending up emotionally and energetically bankrupt.