This is the hopelessness we so often feel when faced with griefs too great, catastrophes too horrible, events too shocking.
In broader events, particularly those that stem from injustice or cultural evil, we must find a way to speak. Most often, we "speak" by shouting across the void to those we despise--those we fault for whatever it is that's causing the disturbance. I submit that it would be more useful to speak calmly and clearly to those who stand nearer to us, if not right beside us. Those with whom we find commonality, but whose messages and methods have descended into madness. Police our own neighborhoods, so to speak. Then perhaps the more moderate voices, those who seek peace, would drown out the hate-driven shouting.
Seem to me that it's worth a shot.
But there are times that we truly ought to remain silent. Because, as Kent Haruf states above, oftentimes words are insufficient. When your friend has suffered a grief too deep for verbal comfort (the suicide of a child; the abandonment of a spouse; the loss of a home to wildfire), your silence itself is a balm.
The trouble comes when we, afraid of the awkwardness we feel in silence, start speaking merely to fill the void. That's when we say things like, "It'll be all right," or "At least [fill in the blank]..." (Seriously, when comforting a friend over any sort of loss, it's best not to start any sentence with "At least...." No matter where the sentence goes from there, it'll minimizing the pain your friend is feeling. Think about it.)
Still worse, we avoid the awkward silence by avoiding the friend. They don't need a reminder, we reason. But honestly: their whole life is a reminder.
The silent presence of a true friend tells the person in grief that you are sitting in their grief with them. Your silence says, "I'm here, however awkward or uncomfortable it gets." With your silent companionship, the burden isn't gone, but it's shared, so it's eased. And that is the first tiny step toward actual healing.