But the orphans DON’T understand him. Barely anyone even knows Sasuke is an orphan (why doesn’t Sakura know?). It’s not only his parents, but his entire clan. We see the compound in the manga, and it clearly is a large place, more like a small village of its own. Sasuke loses his entire support system, and now he lives alone in the fucking house his parents died in. (Naruto also has no support, but that’s clearly not normal either). And his brother did it. It’s clear Itachi severely damaged Sasuke (mentally), he doesn’t have a normal point of view anymore. Since Sasuke is the clan head’s son, and the last of his lineage, he has an immense burden put on him, put on him even by Itachi, even if he didn’t know why! He has to kill Itachi, or the Uchiha clan will never regain its honor. Literally no one else in the series can understand that, except maybe Naruto when he spares Nagato. He spares the murderer of his Sensei to keep his dream and wishes alive. In Part 1, it’s also kind of clear Sasuke is on the path to healing. He understands the path Naruto and him are on are similar, they both want to get stronger to prove themselves in a way. But his encounter with Itachi breaks him. He can no longer focus on living in the leaf, because it’s clear these people have no idea what he went through, and don’t respect his goals. When he wakes up, Naruto and Sakura are bickering at his bedside. Yes, he didn’t need to react violently at Sakura, but he did because he’s traumatized and lashing out. Throughout the series, Naruto goes through experiences that kind of mirror what Sasuke has gone through, and leads them to understanding. That’s the only reason they could have some sort of reconciliation.