His dad had moved out three years ago and moved back in three months ago. Zach couldn't get used to him being around. (2.4)
Zach is having a difficult time readjusting to life at home with his father, but what he doesn't seem to realize is that his father is having a difficult time, too. Granted, Zach's just a kid still, so it's not exactly his responsibility to see things from his dad's perspective.
Zach and his mom had been fine before his father moved back in, and they'd be fine when he left again, too. (2.7)
This is the key to understanding Zach's anger with his father: He assumes that his dad is not back for good.
"Don't bother trying to be my father anymore," Zach said, walking up the front steps and past him. "It's too late for that. It was too late years ago." (2.71)
Zach has plenty of good reasons to be upset with his dad, but we have some bad news for him: Healing the wound in their relationship requires both of them to let bygones be bygones.
When he saw the school building in the distance, he wondered what would happen if he just kept going, the same way his father had left them three years ago. (3.10)
Zach thinks about abandoning his life, just as his father once did. Similarly, Zach's father is mean, just as Zach's grandfather was. Can they find a way to overcome the cycle?
He took a deep breath and blurted out the only thing he could think to say. "I don't want to play anymore." (4.4)
After his father throws away his toys, Zach abandons the game because he doesn't want to tell his friends what happened. Just as his dad radically changed his life, Zach pretty harshly does something similar to Alice and Poppy.
But the driver just took a long look at Zach, Poppy, and Alice and got off the bus. He didn't say or do a single thing to help them. (6.79)
The bus driver's behavior echoes the abandonment that the kids have experienced in their family lives. He just doesn't show up when they need him, leaving three kids to sort through a tricky situation. Maybe he just needed a coffee?
If there was magic… then maybe not everyone had to have a story like his father's, a story like the kind all the adults he knew told, one about giving up and growing bitter. (9.15)
In addition to abandoning their children, many of the adults in Doll Bones have abandoned their own dreams. Basically everyone in this book could use a good pep talk.
"You promised this wouldn't happen!" she shouted. "You promised, and then you broke your promises over and over again, and now my whole life is going to be ruined because of you." (12.26)
Alice feels betrayed by Poppy, who broke her promises, but Poppy's bad behavior comes from a place of fear. She's worried her friends are growing up and leaving her behind.
Although the main street of East Liverpool was full of big store windows and shops, many were no longer open at all. (13.1)
Not content to fill her book with abandoned people, Holly Black included an abandoned town, too.
"I need a ride," Poppy mumbled […] "I couldn't get my dad, and my mom's working until late. She asked if one of your folks could drive me." (14.75-14.77)
Poppy's parents never left home the way Zach's dad did, but that doesn't mean they're winning any parenting awards. They might physically still live with Poppy, but mentally and emotionally, they're completely checked out.