I think most people are listening and interpreting for themselves so what we say, they apply it to their own lives and come up with a response that they would give themselves if they were in that situation. Someone not comfortable with crying, for example, is likely to be the one that says, "Don't cry! There's nothing to cry about" because they are uncomfortable; we all tend to make things about us I think. We don't know what to say because we don't want the other person's difficulty/tragedy so "push away" from it.