Yea, though I walk through  the valley of the shadow of death, I will fear no evil: for thou art  with me; thy rod and thy staff they comfort me. –Psalm 23:4 (KJV) 
For the past three months I  have been walking alongside my wife, Andrea, as she has courageously  battled esophageal cancer.  Her faith is inspiring, amazing, and  absolutely solid.  Even though I have for years preached that our  lives can be turned upside down in an instant, I never fully understood  just how dramatic this turning upside down process can be.  Most  of the time I walk forward in confident faith that everything is going  to be all right; she is going to come through this ordeal, and she will  soon be enjoying good health again.  There are other times, however,  when I waver between blind panic and complete hysteria.  The “what  ifs” of this nightmare, what may or may not happen, bang on my heart  and rattle my mind with their cruel uncertainties, tempting me to doubt  God’s sovereignty and healing power. 
During those moments of fear  I am compelled by the power of the Holy Spirit to not panic, but to  trust the Lord.  This peace that compels me is not my doing; please  don’t think for a moment that it has ever originated in me.   The peace that keeps me moving forward in the midst of this terrible  illness my wife is facing is the pure knowledge that the Lord is with  us.  Christ is with Andrea, guiding, helping, encouraging her every  day, and He is daily coming alongside me with a strong and mighty hand  so that I can be encouraged, but that I might also encourage her. 
This comforting that God has  promised is as real as the ground beneath our feet.  When we feel  ourselves becoming weak with the tears we have shed and the anguish  we have suffered, the Lord upholds us by divine spiritual power.   The picture given in the Psalm is like unto a staff being gently placed  into our trembling hands.  We can lean on it for support, and we  will be able to keep moving forward. 
Perhaps you too are facing  some crisis which has left you terrified and wondering if it will ever  end.  Do not be afraid and do not panic.  Look to the Lord  and lean not on your strength, but on His.  God is perfectly willing  to help and comfort us in our time of need. 
The Lord has promised to guide  us through whatever difficult valley we find ourselves traversing.   That promise still remains.