Is this sexual assault?? Help!

Right now I am 14 and in 8th grade. When I was in 3-4 grade there was a 5th grader we'll call A. She kind of took me in and all of a sudden started showing me a new world. She would show me porn, get me naked, touch me, kiss me, I don't want to get to graphic. I was in third grade I honestly thought it was normal. But she was 12. I was 8-9 (I'm also a girl) and she would touch me, kiss me, basically all of that. I didn't say no or try to stop her. I liked some of it. But I was so young I thought everyone else did it to. She made me think that. She was old enough to know it was wrong. Was this abuse? I