I remember when I first started therapy in college and the first session I talked okay, told my story and at the end of the time the therapist said, "I never heard you mention your father once". I was shocked! Maybe you should deliberately start talking about your father, see where that goes? It could just be that it is not obvious to your therapist that you have a need to talk about your father, especially if you go along with where she leads the conversation. Just say, "No, I'd like to continue talking about my father, I think it's important" if she tries to move it to another topic? If she doesn't work with you then, then you will know that perhaps, for your purposes, you need another therapist?