Why does God allow bad things to happen to good people?

Why does God allow bad things to happen to good people?  For some, this is the biggest question. It may be the one thing that keeps a person from having a relationship with God.  It is often an atheists biggest argument. I have definitely struggled with it before.
"Now faith is confidence in what we hope for and assurance about what we do not see." - Hebrews 11:1, so I know that whatever God does is righteous even if I don't understand it or like it because of my faith, but it's so hard to explain that to someone. I have caught myself doubting it sometimes.
I like to listen to KLOVE radio.  They often have a segment called "behind the music" where there are stories of the inspiration behind a certain artist's song.  So often I hear stories of a terrible tragedy that has befallen one of these artists.  One day while I was driving in my car and listening to one of these stories I thought to myself " Why are these horrible things happening to these awesome Christian people?  They are so much better than me, and look at the tragedy in their lives." Right away I got my answer: that is why they are such good Christians!  
You might be thinking "that makes no sense", so I'll explain. The story of Jeremy Camp's wife, Melissa, particularly inspired me and you can read more about it if you aren't familiar here:  https://www.cbn.com/cbnmusic/interviews/700club_JeremyCamp02122008.aspx . But basically Jeremy's wife Melissa died of cancer and he turned around and made some amazing, inspirational music.  I don't know about you, but I always imagined that if something like that happened to me, how would I go on living?  How would I ever get out of bed and face the day? Let alone stand up and glorify God because of it!  To simplify the thousands of thoughts and feelings I had about that revelation: That is why God let that happen to such good Christians as Jeremy and Melissa; because of that tragedy they were able to bring such glory to God. Jeremy said: "That was such a good act of obedience for me, just saying, 'Lord, I don’t want to do this, but I know this is why I am here.' "
"I remember not wanting to ask God, 'Why,' but I finally did, and God always spoke to me. He said, 'Jeremy, I don’t always want you to know why, because I want you to have a testimony of walking by faith.' And I had written that song previously on our honeymoon, Walk By Faith."
"And I look at these songs that come from it, Walk by Faith and I Still Believe. I wrote two weeks after she went to be with the Lord," says Jeremy. "I have seen story after story of God using this whole thing to show His faithfulness to encourage people. That blows my mind realizing that Melissa made that statement, that if even one person accepts Christ. I hear thousands and thousands of stories. I remember being on my face after that realization and God said, 'Jeremy, 'Remember.' "- from the interview Jeremy Camp: Melissa's Dying Wish by Audra Smith.
Romans 8:28 tells us "We know that in all things, God works for the good of those who love him, who have been called according to His purpose."  Yes it would be so tragic for this to happen, and I'm not saying that Jeremy doesn't have every right to mourn the loss of his wife, but wont it be wonderful when he gets to Heaven to hear his master say  "Well done, good and faithful servant! You have been faithful with a few things; I will put you in charge of many things. Come and share your master’s happiness!" and to meet all of the other people in Heaven who are there because if the message that God inspired in him!