What is a real loss?

What is a real loss.....
is it losing an unborn baby after carrying it inside of you for 6 months.
is it losing a husband in a burning building in which he went into to save someone else life.
is it losing a son or daughter in an accident in which they had no part of.
is it losing a brother or a sister to alcohol or drugs of any kind.
is it losing a friend to a disease that you can not fix.
Or is a real loss watching your son die on a cross to save others of their sins