Hi Hopeangel:
I am the wife of a crack addict. Tatics are the same. You may want to look in the front of your phone book and see if there is a special feature to block the call. Even though it is restricted from showing on your caller ID the computer should be able to block.
This may serve two purposes for you. One it may help to calm how you are feeling now and two it may force the frantic caller to try another way to get in touch and reveal more to you about what IS going on.