This movie bring so much tears, making any of us who watch this movie would want to fall into despair and hopelesness of the cruel fate of the world. But please know this, this movie ended with happy ending.
It's a matter of perspectives the MC's sees, by the start of the movie his life ended, finally he able to meet his litle sister again and relieving his times in life with her. Then, telling us how he spent his life.
Just like us in our reality. Looking back at lifes we've lived, no matter how bad it is, all that had happened was a precious momments in life.