Resetting password
The account uses the email the account Serial Key was registered to, not the email ‘it’ was sent to. Your girlfriend (or you) should have registered the account, and chosen the email (account name) at that time.
As for the issue with resetting the password, you will need to request assistance from the CS Team (as instructed). Top of Page – Support – Submit a Request. (Make sure to choose an option from all drop-down menus.) Your girlfriend, and only your girlfriend will need to contact support and discuss her issue(s) with a Team member.
Good luck.