After first appearing as Bucky Barnes and coming to Steve's aid in Captain America: The First Avenger back in 2011, Sebastian Stan has become a fan favorite MCU actor throughout all of his appearances in the MCU. Not only has he undergone a physical transformation since his debut, but his character has also grown stronger since his time as the Winter Soldier.
Even though the Hydra words are no longer in his head, Bucky still struggles with the murders that Hydra made him commit to this day as is evident in The Falcon And The Winter Soldier. It's because of this deep pain that Bucky has given us some of the saddest quotes in the MCU.
"Stop."
One of the negatives fans pointed out at the time of Captain America: Civil War was Helmut Zemo. Although Daniel Bruhl did a fantastic job playing him, there were some fans who thought he was a weak antagonist compared to some of the other MCU villains.
When Zemo got a hold of Bucky he started to say the words that activated the Winter Soldier and as soon as he said "Longing" in German Bucky knew what was about to happen and did not want to return to his brainwashed murderous self again.
"..But I Knew Him."
In Captain America: The Winter Soldier, after Steve and Bucky's first fight on the bridge and Steve exclaims "Bucky?!" fans can see Bucky display a look of confusion signaling that there is something more to the identity of the man he just fought.
When he returns to the Hydra base with Alexander Pierce he pleads for information from those around him and when they try to hide Steve's true identity, Bucky is so sure and says "...but I knew him." The longing in Bucky's voice for everything to make sense is truly tragic.
"Steve..."
In Avengers: Infinity War fans will remember Thanos managing to snap 50% of all living creatures throughout the universe out of existence as they all turned to dust. One of these fallen heroes was Bucky Barnes.
Some people would scream in fear, but Bucky chose his final word to be that of his best friend, thinking it was the end of the line.
"To Do What?..."
Bucky's latest appearance is in the hit Disney+ show The Falcon And The Winter Soldier where he is coming to terms with the acts he committed as the Winter Soldier. After fighting to save billions of lives the president pardoned Bucky with the condition that he attend therapy.
In episode 1 Bucky's therapist tells him "You're free." and Bucky not knowing how to move forward with his life simply says "To do what?...". Fans certainly felt for Bucky at this moment.
"I'm Not Sure I'm Worth All This Steve."
In Captain America: Civil War Bucky is one of the triggering factors of the fight between Captain America and Iron Man. With Peggy gone, Bucky is now the only connection that Steve has to his past and, as his best friend, protects him at all costs which includes fighting against his friends and fellow Avengers.
While Steve and Bucky are on the Quinjet to travel to fight the other Hydra soldiers, Bucky understands that the rest of their team will probably go to prison for their actions in protecting him. With all that Bucky has done, he says "I'm not sure I'm worth all this Steve." His struggle with his own self-worth is incredibly tragic.
"I'm Gonna Miss You Buddy."
In Avengers: Endgame, as confirmed by the writers, Bucky knew that Steve was not planning to return after taking the infinity stones back to their original locations, and fans could feel the emotion in their final discussion.
One of their iconic exchanges "Don't do anything stupid till I get back." "How can I? You're taking all the stupid with you." also features in this conversation just before Bucky's final words to Steve "I'm gonna miss you buddy." This scene is also very sad because Steve is, essentially, abandoning Bucky shortly after they were reunited.
"I Know. But I Did It."
Steve tries to reassure Bucky that his actions as the Winter Soldier were not his fault by saying "What you did all those years, it wasn't you. You didn't have a choice." It doesn't take long for Bucky to respond with "I know...but I did it."
Steve has no response to this, but nonetheless, Steve still believes that Bucky is a good person. Bucky, however, is weighed down by the guilt of everything he did.
"I Had A Little Calm In Wakanda, And Other Than That I've Gone From One Fight To Another For 90 Years."
While in therapy in The Falcon And The Winter Soldier Bucky points out a fact that might not always be apparent to fans as they watch the movies. He reminds fans that ever since 1945 Bucky has gone from one war to another.
First in World War II, then to fighting as the Winter Soldier, then to fighting against Iron Man, to fighting Thanos and his outriders and then returning in Avengers: Endgame to fight Thanos again and now the Flagsmashers. Bucky's only time to have any sort of break from fighting is during his time in Wakanda.
"I Remember All Of Them."
In Captain America: Civil War, Zemo finishes off his plan and sparks the final fight between Tony and Steve by showing Tony the footage of Bucky killing his parents.
Tony manages to get a hold of Bucky at one point and says "Do you even remember them?" Bucky replies with "I remember all of them." signaling to everyone that he still retains his memories from his time as the Winter Soldier and all the people he has killed.
"...And If He Was Wrong About You Then He Was Wrong About Me."
One of the most powerful lines so far from The Falcon And The Winter Soldier came from episode 2 when Sam and Bucky both attend a therapy session after Bucky is freed from jail.
Steve believed that Bucky was a good man despite everything he had done, and Bucky is worried that was he was actually wrong about him being a good person after all.