So I gave my best friend my Acc but now we're no longer friends but she uses it winter what can I do about it
Change Password? What's so difficult?
Change password, say that you should no longer use it.
Change the password.
https://www.netflix.com/...ourAccount
Change password and then log out of all devices.
Either you talk to her and tell her you don't want her to continue using your Netflix Acc.
Or you say nothing to her and just change your password.