And due to the conflict with Teddy that leads to the nuclear apocalypse in season 7, she has not had time to properly process her loss. Not only has her daughter died, but for all she knows, the hope for a brighter future has died along with her. Losing Athena has completely broken Grace. As a result, hearing the song reminds her of what she's lost explaining her reaction in season 7 episode 2. When addressing why Grace refuses to listen to the song, it's important to note which song it is, that being Roy Orbison's "In Dreams." This song plays when Grace loses Athena, and beyond that, it plays throughout Grace's dream. Related: What Happened To Fear The Walking Dead's Zombie Baby?
In one of Walking Dead's darkest endings, after spending the episode dreaming about the optimistic future she will bring, Grace ends up losing her daughter, Athena, with the baby becoming stillborn. Instead, it is revealed that Grace is pregnant, and for the majority of season 6, Morgan makes it a priority that Grace can deliver her baby safely. Throughout season 5, Grace suffers from radiation poisoning, and towards the end seems to be succumbing to her illness. Season 7, episode 2 shows Grace in a dark place, and that is largely due to the events that occurred in the past two seasons. While this seems trivial, in hindsight, there's actually a lot more to ponder about Grace's reaction to that particular song. This happens while she and Morgan are traveling with baby Mo through the nuclear wasteland in search of a safe haven away from fallout. Fear The Walking Dead's "Six Hours" sees Grace not want to listen to a song playing on her mixtape and aggressively try to shut it off.