'Why, then, 'tis none to you, for there is nothing either good or bad, but thinking makes it so.' -- Hamlet
Just as our muscles can not grow without strain, so too do we need struggle to evolve in our lives. The trick is that we can choose to see the inevitable struggle as a good thing or a bad thing.
Remember that Buddha said all life is suffering, but he also advised us to find out purpose and enjoy the struggle.
That being said, I think we should always be mindful to balance the challenges that the Universe brings to us with the challenges that we, or others, bring.
This is a very fine point, but for those that can see, it is as obvious as an upvote.