For the entire two chapters, Eliphaz starts by asking Job to be patient while he speaks. Then, he goes on and on about how Job has been a rock when others have failed, that he has always supported others when they have been down.
So why the long face now?
It's easy for one who has not experienced pain to preach to them, telling them to keep their chin high. Ever since my late wife was diagnosed with leukemia and had lost much of her eyesight by October 2011, she has experienced more pain than anyone I had ever personally known. I saw the pain up front. Not once did I tell her to keep her chin high. I comforted her, cherished her, loved her.
I'm not saying what Eliphaz did was wrong. He just misunderstood Job's pain. It isn't until the 8th verse in chapter 5 that he finally says: "If I were you, I would go to God and present my case to him." He goes on saying that God does great things too marvelous to understand, countless miracles, gives prosperity to the poor, and even protects those who suffer.
Pray to God. That is what my late wife and I did. We prayed. We prayed for her to be healed, day after day. In the end, she was finally released from the pain when she went to Heaven. Honestly, it wasn't the outcome we were hoping for. But we also had faith that our lives were in God's Loving Hands. He knew best.