Can I get guardianship of my niece if the grandmother adopted her?

Grandmother adopted niece after the child lived with me (Aunt) for 6-7 years. She lied to the courts about the living arrangements. She is 12 years old now. And wants to get away from the grandmother who is mentally and emotionally abusive. She sees therepists and counselors and physachrists (?) And they believe the grandmother. I have recordings of her telling her she is a waste of air. A dog. And more .She has to sleep on floor and not allowed in her own room cause it is messy. She has one time been physically abusive and left bruises on her face and I have those pictures. Children services never spoke with me or even tried to contact me. She has called me Mama since she started talking and still does altho I am her aunt.