Having expectations that life should be a certain way only leads to disappointment. Resistance to reality creates anger and frustration, and doesn't change your circumstances at all. Acceptance of life in all of it's glory and darkness without judgement of "good" or "bad" can lead to peace. This acceptance doesn't mean that you don't have the power to choose your reaction to circumstances - that is where your true power lies. However you don't have to waste your precious energy trying to change the nature of things. There is value in all of what life presents us with - it is still a gift, even in our darkest moments.