Because we aren’t believing much of anything not even those closest to us.
Jesus understood this. His best friends didn’t believe him after spending 3 years of intimacy with him. He told them over and over he would return and yet they spent the entire weekend of his death whining and whimpering that he was gone. (John 14:28)
Instead of believing his words prior to the greatest weekend in history they chose to ignore them.
Why are we shocked when others don’ believe us especially those we are close to?
Maybe God wants us to know how he feels.