HELP HELP email junk

I am really getting tired of opening my email.  Someone has gotten into my email and stole my address book and now are sending Viagra adds to all my friends, how terrible, I have ran all kinds of scans to protect my computer, but they still get in. 

Being a writer they say get out there on the internet and let people know who you are, the more followers you have the better!  Yea right??? I don't want to know how to enlarge certain parts of a mans body, or get some money from someone overseas to hid in American to be ripped off, every day it a poor or lady or the military that has something they want me to send my name & bank account information too. You have to be joking I can't stop all these email from coming to my junk mail.   If I change my email address I have to let everyone know how do I know I am not letting the thief know too? If anyone has the answer please let me know. cherie