Nico really wants to keep everything to himself. Tell nobody about his plans to get away, and nobody can betray him to his dad. Again.

(There were several prior incidents. He still shudders about the most recent one, where he tried to make it on his own, and did build a shelter out in the woods, but nobody in town would give him work or sell him food saying to just go home instead, and cold and hunger drove him back into Father's house. And not without punishment.)

-He would keep it to himself, but she will not leave him alone. He tells Lenora. He's gained a single lonely mote of magic, recently. He's going to burn his magic, what little he has earned, sacrificing it permanently to get AWAY, far enough away that - that - things might be okay again. That he'll never have to think about Father. Or Mom. Mom is kinda alright. But only kinda.