"If you only knew..." God says with the tears of Jesus in Luke 19:42 that I am held accountable for what I refuse to see or am unable to see.
Sometimes God opens a door I refuse to go through. And when God shuts a door, that door will never be opened again. There will be other doors, yes, but it serves to remind me that sometimes doors are shut that never needed to be if I had only gone through them while they were open.