Neon Dies At Dawn by Andersen Prunty
A retired man loses his wife to cancer and his daughter to a mysterious accident. He mostly lives alone, occasionally taking care of his grandson. When he sees a black van drive over a young woman before disappearing into the dark of night, he loses what little faith he has in humanity and discovers a sense of vengeful purpose. Now he’s in danger of losing himself to long-repressed demons and a terrifyingly bizarre world that has always surrounded him, a world he’s spent his entire life keeping at a distance.