I have told him "don't smile" quite a few times

That's the thing. My therapist wants me to let myself be angry at my mom but she really does try and she is a good and understanding and compassionate person.
In other parts there was some defensiveness, like focusing on how difficult the situation she was in was, as if she had no choice. That's frustrating for me, because, yes, I know she was hurting and traumatized, and that doesn't mean she wasn't responsible for her actions and how they affected her children.
Her focus is on how my father hurt both of us, but she doesn't fully acknowledge how her actions in response to my father also hurt me, or at least minimizes her own agency in the situation.