Catholic writer Frank Sheed in his book "A Map of Life, a Simple Study of the Catholic Faith" writes this:
"Thus the effort of men to relax the moral law so that others shall not suffer unduly is aimed at altering the test devised by God himself . . . Life is not only a testing to see if a man is fit, it is likewise a preparation to make him fit.
I love this quote. It brings to mind all the reasons that God places sufferings in our lives. He knows what it will take to sanctify our souls, and every obstacle we encounter, every bit of suffering He places before us, we should remember to use it to our advantage. He gives us the appropriate amount of grace and sufferings for each of us to attain personal sanctification. How often have we failed to recognize these graces and wasted them by forgetting to offer up our sufferings and annoyances? Life is a preparation for heaven, and God has provided us with the graces necessary for salvation. Suffering is one of those graces.