Stepdaughter troubles

Are there any other step moms out there that sometimes have trouble loving their step kids sometimes? I have an awesome little girl in my life. She's 10, I've known her 5 years. But everything out of that kids mouth is make-believe. She is a master manipulator of the adults in her life. She makes up dramatic crying stories about her step-dad hitting her, kids at school bullying her, her mom saying awful things about me... It gets all of us riled up then we find out they're lies. Okay I'm rambling. . Hopefully someone can relate