Moe,
In October of 2003 I stopped to help at an automobile accident in rural Nevada. I was not involved in it, but I did see it happen. I was one of the first people on the scene. The young woman, a 25 year old stranger, died in my arms. She was the eldest daughter in her family.
I was able to meet her family, devout Catholics, about 2 weeks later, to explain what happened and help put up a roadside memorial. Their grief was like your grief.
At the time I was an atheist. However, that very night after meeting her parents, God performed a miracle and I had a sudden and miraculous conversion to the Catholic Church. Part of this miraculous experience included these words spoken to me. “No death is empty if it brings someone closer to God.” Just looking at this thread, it is clear many people have come closer to God.
May God bless you and your family. May He grant you peace of mind and wipe away all your tears.