Life isn't easy for droids in the Star Wars universe. While many of them seem to be sentient beings, droids are often perceived as emotionless machines who merely exist to serve their masters, leading them to endure prejudice from others. Interestingly, however, the Skywalker family is one of the exceptions to that rule and have typically treated their droids like family, often putting themselves in danger to protect their robotic companions. Even so, that hasn't stopped C-3PO from suffering nearly as much as the Skywalkers have over the course of their adventures together.
C-3PO's history with the Skywalkers goes back to The Phantom Menace, in which a young Anakin Skywalker assembles him so he can help the boy and his mother Shmi with their household chores. Although he's more concerned than comforted when Anakin assures him Shmi won't sell him when the pair part ways, by the time he and a now-grown Anakin are reunited in Attack of the Clones it's implied C-3PO has led a pretty gentle life under Shmi's watch. Of course, everything changes when Anakin, Padmé Amidala and R2-D2 bring C-3PO along on their rescue mission to the planet Geonosis.
Upon arriving on Geonosis, C-3PO inadvertently ends up in a battle droid factory and is subsequently disassembled, leading to his head getting attached to a battle droid body while a battle droid head winds up on his body. This turn of events is played for laughs in Attack of the Clones but it only marks the beginning of C-3PO's torment in the greater Skywalker Saga. Indeed, after having his memory wiped in Revenge of the Sith, C-3PO is put through the ringer in A New Hope as he and R2-D2 flee to Tatooine and are captured and traded by Jawas followed by C-3PO being heavily damaged by a group of Tusken Raiders.
What's more, there's a pattern of C-3PO being taken apart over the course of his life. Most infamously, in The Empire Strikes Back, he gets shot to pieces on Bespin and has to be carried around in Chewbacca's backpack for a significant amount of time because his arms and legs have not yet been reattached. Years later, as detailed in the 2016 comic book Star Wars: C-3PO, the plucky protocol droid participates in an all-droid Resistance mission that results in him losing his left arm. And while he would've preferred one that was golden, he ultimately replaces his lost limb with a red one from Omri, another droid who sacrificed himself on the mission.
Moreover, just as organic sentient beings accumulate mental trauma for reasons unrelated to physical injury, C-3PO has gone through his fair share of emotional and psychological pain, even when he's not being violently disassembled or narrowly avoiding being killed. He might not remember Anakin due to his memory being erased, but C-3PO was surely impacted emotionally by Ben Solo's fall to the Dark Side since he knew him his whole life. Luke Skywalker's subsequent decision to go into self-imposed exile couldn't have been easy on C-3PO either, especially since R2-D2 went into low-power mode right after.
If all that wasn't enough, C-3PO willingly agreed to have his memory wiped a second time in The Rise of Skywalker, so he could translate the inscription on a Sith dagger that will lead to the location of the resurrected Emperor Palpatine's Star Destroyer fleet. It's a particularly noble sacrifice on the part of C-3PO, who's under the impression it will erase his memories for good. Fortunately, for him, R2-D2 is able to restore his memory from an earlier backup, allowing C-3PO to join in the Resistance's celebration of their victory over Palpatine and the Final Order -- a victory that wouldn't have been possible without him.
As much as the Skywalkers went through in their efforts to restore peace and freedom to the galaxy, C-3PO has been right there with them the whole time. It's easy to dismiss him as a comic relief sidekick who frequently gets on others' nerves (and not without fair reason), but in many ways C-3PO's unexpected hero's journey is just as compelling as the stories of those around him, and a reminder droids are not "made to suffer," as he once famously bemoaned. Hopefully, life will be easier for C-3PO when he and R2-D2 get the spotlight in the upcoming animated series, A Droid Story.