I love that the father is genuinely a good man and a hero, who, in the midst of an illness that's taking his mind, runs toward the sound of danger because he instinctively wants to protect people. It makes Selena's resolve to love and help him all the more compelling, instead of the old "everyone is crap except the lead character and the love interest" trope I see far too often. Also, it really hits in the feels when she berates herself for "not being good enough," because I'm certain if her father were well, he'd be horrified his daughter thought of herself that way.