A funeral can be a great help to people who are grieving. A funeral can also make matters worse. A funeral can be built around the strong Word of God, helping people face death, while serving as a catalyst whereby sorrow is resolved into hope. Or it can open all the wounds, cause people to cry even more, and stir up their sadness. The first kind of funeral works by cultivating faith. The second kind works by creating a catharsis, so that the grievers simply cannot cry anymore, are emotionally burned out, so that, out of that numbness, they can get on with their lives.
This is not a matter of denomination. A funeral that follows the Lutheran Order of Christian Burial will be the first kind, though the most painful example of the second type that I have experienced was in a Lutheran church.