Or is it possible that I don't have to, but instead still use the same GAG account?
Most Helpful Girl
Changing your email address is no problem, no need to create a new account with us :-)
If you go to My Settings from your profile, or Settings from the drop down menu (top right, hover over your username), you'll see a section there labeled Login Settings.
Enter the valid, correct email address there where it says Email and click Save.
You can find these steps in our FAQ as well - http://www.girlsaskguys.com/faq0