After they bug out of Yavin IV and join the Rebel Fleet, Chewbacca wonders if maybe, just maybe, Han, Luke, or Leia would actually talk about their respective horrific ordeals, as a Wookiee would, as any emotionally healthy and adjusted being should. Though he'd pretty much given up on Han over the years, he'd hoped that maybe the other two would exert a good influence and own up to the nightmares they're all having and the screams and crying he overhears when he takes over the Falcon's third watch. But after two hundred and thirty three Kashyyyk years, he's learned that Humans, and especially young Humans, and by the Trees, these three are so young, are terrible at confronting their past trauma, always, always deluded into thinking that, so long as they don't stop, they will never drown.
By the Trees, they never learn -- Star Wars OT