If she cannot log into your Gmail account, eventually Facebook is going to send a message to your Gmail account asking her for verification. Just let the verification emails sit without clicking on the link, and her Facebook account will eventually be removed.
I received an email that I created a new Facebook account, but I didn’t sign up for a new account.
Most likely, someone tried to sign up for a Facebook account using your email address by mistake. The sign-up process isn't finished until someone clicks the link in this email, so the easiest thing to do is ignore the email. You can also:
- Click the link at the bottom of the email to let us know this wasn't you
- Add this email address to your account, if you have a Facebook account
- File a report
You must be logged into Facebook under your own account to access the help page.
If she can access your Gmail account, change the password as soon as possible and go through the steps above with Facebook.