my middle child (almsot 10) is like this sometimes when she comes back from her dad's house.
Basically, what we do is remind her firmly that she WILL be respectful or suffer the consequences. If she calls names (she called her sister an idiot for leaving their shared bathroom to give her privacy while she went to the bathroom - obviously her sister was being respectful of her privacy) she gets a 'pleasure item' taken away; computer, guitar hero, nintendo DS, Hannah Montana show, etc.
Your daughter needs to learn that she cannot be disrespectful to you or others in her family. I would suggest finding out why she finds it so easy to hurt people who love her, and see what's bothering her. 'something' has to invoke this behavior... find out what it is.. talk to her - it might take a few times to really get to the bottom of it, but I tell my kids, this is our sanctuary from the rest of the stress out there.. school, mean people, traffic, work... we have to find a way to leave the garbage at the door and find peace here.... if that means you need to tell me how crappy your day was, lets talk over an 'after-school-snack' so you can feel better and get on with being happy to be home with people who love you.
Sometimes i noticed the behavior gets worse because it's allowed to continue... she's used to being abusive, so it will take a little work to get her out of the 'habit'.
stand your ground mama.. good luck