Random emails not making it to my inbox.

I'm encountering the same problem as Michael.  Emails from my brother and my daughter are not making it to either my inbox or my junk folder, but I'm getting sale alerts from Chico's, JCPenney, etc., etc.  Why would contacts I've had in my account for years all of a sudden not come through.  VERY frustrating!  As Michael said I don't know what I am not getting.  Any ideas how to resolve this issue will be greatly appreciated.  And yes, I have already tried all of the troubleshooting ideas given to Michael.  Thank you.