Mail is defaulting to old wrong address

My girlfriend is emailing my old address from her mac using mail.
She said in address book my old address is deleted but when she types my name the old one pops up as the primary.
Any ideas how to clear that?
Thanks

Thanks!
I pulled this outta Mail Help:

To manage addresses in your Previous Recipients list:


Choose Window > Previous Recipients.


In the Previous Recipients window, do any of the following:

■
To sort the list by name, email address, or the date the address was last used, click a heading.

■
To search for a name in the list, enter the name in the search field.

■
To remove a selected recipient from the list, click Remove From List. Removing the recipient is useful if you don’t intend to use it again or if you previously mistyped an address and want Mail to stop suggesting it as a matching address.

■
To add a selected recipient to your address book, click “Add to Address Book.” Addresses that are already in your address book have a card icon next to them.

To select addresses that are next to each other in the list, Shift-click; to select addresses that are not next to one another, Command-click.

You can remove a recipient from the list when you send or receive a message by clicking the arrow in a Smart Address and choosing “Remove from Previous Recipients List” from the pop-up menu.

Great idea, thanks for the tip! 🙂