Do teenagers ever have any redeeming qualities? Totally kidding! I think the events which have happened and are yet to come are shaping the boys, it just takes a while. Introspection will come, sometimes from the unlikeliest of places. Dustin and Brett are obviously trying to push the other out of Billy's life. But are they doing it so that they can have Billy all alone, because they really think the other one is bad for Billy, or simply out of spite?
As for there being no consequences for Billy's actions at the hospital, well, maybe. They did have him strapped to the bed overnight, and don't underestimate the power of Jen Reilly's influence. But overall, yeah, that's Billy's life for you. "You just punched a mirror, but you're walking so it's okay. Move along." Is Billy really paranoid or is life truly out to get him?