Any additional email addresses can be deleted by following this support article under the title "Delete an additional email address". You are also able to delete any rescue email addresses under the title "Delete a rescue email address".
About your Apple ID email addresses – Apple Support (UK)
In addition, change your Apple ID Password and Passcode.
Change your Apple ID password - Apple Support
Set a passcode on iPhone - Apple Support
With your Apple ID and password, she would be able to change and edit photos or other information stored in iCloud. Many things can be done with your Apple ID and Password including locking you out of your own device. The situation of the OP of the phone unlocking to a screen in middle of an action cannot be done remotely and would only be possible with physical access to the device.
I recommend you run the Safety Check that is on your phone to also very Trusted Phone numbers linked to your Apple ID and view who else is logged into your account.
How Safety Check on iPhone works to keep you safe - Apple Support
After this is done, she would need to know your Password and/or Passcode to make any changes to your account.
