"Why do bad things happen to good people?" I used to get so annoyed when I would see people operate with evil/mean purposes in mind who seemed to get away with it an prosper, while I followed the rules and all I got was bad stuff as my reward.
During the last stages of my dad's life, my mother, brother and sister-in-law kept a daily vigil for 3 weeks by his hospital bed. Our routine would begin with my arrival at 10 am, my brother would get there midday and my sister-in-law would come between 4 and 5 pm (my mother stayed with my dad 24/7). My brother and I would wait until his wife arrived and we'd go together to the hospital cafeteria and force ourselves to eat. It was also a time to get away from the room housing the reality that my father would not leave alive.
One day we were in the cafeteria making some jokes and I said "I can't believe I'm here, in this space, at this time." What I was really saying was: "I can't believe I'm spending most of my day in a hospital helping my father through the dying process." I was at a complete loss. None of it made sense. My father was a Hero to many people. He supported everyone and if he caught your vision, know that you would believe through his eyes that you could do anything! He was devoted to God, family, friends, and his church. Why would a vibrant man of God be lying in a hospital bed in the final stages of life? It just didn't seem right. Then my brother made it clear. He said "maybe it's so that we can help someone else through this."
I had learned early on that the best thing a Christian can do is live a life that will be an example to other believers (as well as non-believers) of how to respond to trials and perhaps give them the courage to face them.
By continually building up your trust in God, you'll find that He'll give you strength to withstand every burden of trials that you'll face. "Why is this happening?" To increase your strength in God and to be used as a vessel of His faithfulness.