There was a price for peace, and it wasn't worth paying. That is what Darth Vader decides aboard the ship where he gains his black armor, and when Obi-Wan dies in front of him before the red lightsaber blade can cut into the exiled Jedi Master's skin. Peace is not worth the millions of people affected, the billions of casualties, and possibly even trillions of lives lost in the name of the Galactic Empire's hostile takeover of the dying Galactic Republic. The thought harkens him back to the Sith creed's first tenet, which has remained at the forefront of his mind since childhood despite not knowing it at that time: peace is a lie.
What has he been fighting for, then? Peace is a lie, and cannot be achieved. His life is about bringing balance to the Force; does that mean that he is, himself, a lie? That all he stands for, all he knows and understands, is untrue?
Does it mean that he became who he is under false pretense, led himself down the path of death and destruction, iron and evil, for nothing? He has become more machine than man, but could it be that he was wrong to allow a vision of peace to cloud his mind? All he wanted was for Padmé to be safe! For their child to be safe!
Years pass, and Vader's unanswered questions pile atop one another; they do not forgive him, or forget him, and he returns the favor with ungodly rage and hatred at the galaxy, at Sidious, and at himself. He strikes with all the violent power of the Dark Side, killing people and sometimes whole species in droves...but nothing sates his desire for destruction, save for the one thing that he will not allow himself to do.
His personal TIE ship hovers outside of Naboo airspace after what happened on Bespin, but he does not go down. He can't allow himself to. The people there will fear him, not love him as they once did. He can't betray his love for her, or her trust in him; he will not go down to the surface and begin another genocide...he won't even go down, after all these years, to visit her grave. And that is how he knows he is in the wrong, that his choice was the bad one, that he must do all in his power to save Luke. They are father and son, and surely that must mean something to both of them. Neither knew their father, but one of them has the chance to do so; Darth Vader himself has no father, only a dead wife and a pair of estranged children.
Because he will not go down to visit her final resting place, he knows himself for a coward. Peace is a lie, a bitter remedy for a misdiagnosed disease, and not worth the price he paid with his mind, body, or soul. It is the coward's way.
As he lays dying, staring at his son after redeeming himself by slaying the Emperor, he knows that his cowardice and his questions and his false peace are fading. They are replaced by the ghostly and translucent arms of a lover, a brother, a mother, a father, and a leader...and so many more. Qui-Gon claps his spirit on the back as it's time to go, a congratulations for fulfilling his destiny as the Chosen One and bringing balance to the Force at long last. Obi-Wan hugs him like a bear, looking as though he were in the prime of his life, and he gives a smile. Yoda simply bows his head to the Chosen One, the only Jedi that Vader never got the chance to duel against, and the small creature gives a great smile that makes his ears rise.
All of his worries and fears subside when Shmi holds him to her, making him feel like a child again, and he doesn't entirely dislike the feeling. As much as he missed the Jedi Masters and their presence, he has missed his mother more; not counting her death, the last time he interacted with her was more than three decades ago, and the pain of losing her had never faded...but now she is here again, with him, forever.
The Force surrounds him, his true father with him and his entirety, and he accepts it. He is the son of no man, the child of blackness, rage and hatred made into flesh and metal; that is his truth, and he must accept it before he can see his last ghost, his true haunting, the one whose memory has stained his life for close to its whole.
Padmé brings his now-blue head down, leaning in to kiss him. She is just as beautiful as he remembers in his visions and his dreams, his waking and sleeping nightmares; now that she is with him again, never to be taken away, he will not let her go. He made that mistake once before, and won't do the same thing again.
There is no emotion, there is peace, and it's well worth the price he paid for it.
