How to remove the contacts
Yes, it's possible. Probably creating your second email ID or creating her fake email ID will be the easiest solution. But try this - 

With each Google account you have privilege to Sync only thing you want. I better recommend you to go to Settings on Android, then tap on Account > select Google and tap on your email ID and turn off Sync Contacts. I read it on Selective Sync Google Account Settings and I believe that should work.