Well I have some ideas.

First of all, it may benefit you to find a way to befriend her in some ways.

I don't mean not exherting any parent or role model status to her at all. Moreso what I mean is the best way to reach a child, is to be a child yourself.

Ok, let me clarify that again lol before people think im...er.. crazy :P

what I mean is find something that she loves, something that shes passionate about. Maybe its horses, maybe its reading, maybe its clothes.. and whatever it is, engage in it with her. Find openings in it to talk about how she feels and why she acts out.

for example - child likes barbie dolls. you and child play barbies. Child acts oout a scene where one of the barbies gets really angry -
You could use this to say something like "hey, you know the other day/today/whenever when you got really angry, what made you that angry?

and then, what I usually try to do is share something from my own experience from a similar trying.

For example. I might say " you know, one time blah blah blah happened, and I got SO MAD that I blah blah blah. But now that I think about it, it might have been better if I blah blah blah.

These moments are few and far between, but you have to grab them when they come up.

Try and remember too that a childs mind, no matter what they think, works a little different than an adults.
hope this helps.