Your daughter has not suddenly woken up one day at the age of eight and decided to be a demon. This behaviour has been developing, and you appear not to have taken steps to remedy it at appropriate times.
First of all, you have to take control away from her, and establish your rules as her parent.
You need to sit her down and have a conversationa long the following lines -
I love you very deeply, and always will, no matter what you do, that will never change because you are my daughter.
The way you behave sometimes upsets and hurts me, and I really want you to try and change, and be nice, so from now on, we are going to behave the same way towards each other.
Every day that you are nice and polite and kind, I will be the same, and after Monday to Friday, we will have a treat on saturday as a reward.
Every day that you are nasty and cruel, I will be the same, and I will stop feeding, you, I will take the bedclothes off your bed, I will stop washing your clothes, I will refuse to speak to you, and if you use violence towards me, I will return it, bearing in mind that i am a lot bigger than you.
Now - what I really want is the nice way of us living together, and that is in your hands, so you can control how nice we are to each other.
If you take the nasty path, be aware that i can always be nastier to you than you are to me, and I will be, until you start to be nice again, at which time I also instantly srtop being nasty, and become nice as well.
This is because i love you, and i want us to be loving with each other.
That is what i want, and if I have to live the nasty way, it will hurt me and make me sad, but it will make you more sad, until you decide to be nice again.
ctd.