This is the "hardest" reason to be thankful--to date. But I am so thankful for the times of pain and hurt in my life, both deserved and those times when it was undeserved.
I remember almost five years ago when someone I dearly loved perpetrated great emotional harm to me. Lies were told, propagated, and enhanced against me...and it devastated me, emotionally.
I cried many long days, and even longer nights. I felt my heart literally being ripped out of my body, and I lay bloodied on the ground. (While all of this is very figurative, it would not have been any more painful, had it been literal, in my opinion.)
About 2:30 a.m. one Friday morning, I woke up, and heard the voice of the Holy Spirit say, "Let it go. Give it to Me, and let Me handle it. I will take care of it. I will take care of you. But leave it alone and let it go."
I knew, then and there, that I had no choice but to "leave it alone." And by "leaving it alone" that meant that I couldn't say anything more about it...to anyone...that I would intentionally bless those who had harmed me, and would ask God to help them, no matter what happened to me.
To this day, I pray for this person, and love them more and more--even though I'm never around them anymore.
I look at the pain that Jesus bore for my salvation. I remember the Cross, and remember that I am called to come and die...