I think Annelise's speech about the stereotype of violent black men and white people was foreshadowing and it will be Nate who kills Miller, but it will be either and accident or misunderstanding. I think she and Teagan will learn that the governor did indeed kill Nate Sr, but before they can, he thinks Miller (whom he considers a friend) did it. So, in a rage, he kills him or accidentally does. Frank is supposed to prevent this but does not. He tells Annelise this and this is why she slaps him or maybe Frank and Bonnie have trouble preventing Nate from not turning himself in. Hence why Annelise would break down in her home. Not only has she lost her face case, but she's also lost Nate, whom she actually does care for deeply. He is kind of her "heart" on this show. That would mean she's lost, in a short period of time, her husband, her home, Wes (her surrogate son), her practice, and her I guess lover? or idk maybe Oliver snaps and she's shocked because he's nice.