A famous man once said that we kill what we love, what we hate, and we kill whatever else happens to fall in between the two categories.
Well, perhaps he wasn't so famous...but Darth Vader was sure that he'd heard the Emperor speak of that man in such a way. He truly thanked that man then and there, whoever he was, for giving the Sith Lord the advice which he'd so desperately needed. It was what allowed him to go across the Executioner with peace of mind and purpose of action; for the first time in nearly two decades, he held those two things at the forefront of his thoughts.
He doubts that those who he slaughtered will ever forgive him, if they are watching. He doesn't truly care for redemption, at this point. He understands that this will be his monumental blow, his greatest triumph, a last hurrah for the era that could have been. He will do what he does, and he will do it to protect...but this time, he knows, he will succeed in using his power to be a savior. He is the Chosen One, and he will fulfill his destiny before his time comes.
He failed to save Qui-Gon, on Naboo, so long ago...and he had been unable to prevent his mother's death. The fact that he couldn't save himself was terrible as well, but he truly and completely regrets his greatest failure: protecting Padmé, his beloved wife, from her death.
A death, he constantly reminds himself, that was brought out of his desire to protect.
He had turned to the Dark Side with only his fear guiding him. He loved Padmé, (he still loved Padmé, he sometimes admits to himself,) and wasn't willing to lose her. He had needed the power that the then-Chancellor had offered, or so he believed, because with that power came the knowledge of how to prevent death. With that power, he could not only protect Padmé, but save her. With the power of the Dark Side he would be unstoppable, a bastion of power that would prevent any harm from coming to his wife or unborn child.
How ironic, then, that it had been that very power which had driven a wedge between them and caused him to become hateful. In his drive to protect, he had destroyed her will to live and caused the death of the one who was most precious to him.
When this is over, he resolved a long time ago, he will go to Naboo to live out his days in quiet solitude. It will be as though he never existed; he, with his unsurpassed mastery over the Force, will be able to hide from all but the senses of his son...who he will soon fight for. He knows the Emperor's plans, as well as the Rule of Two. Sidious will not merely step aside to allow a new era to be ushered in, if Luke falls to the Dark Side, but rather have father and son fight one another to the death.
That, above all else, is something that Vader cannot allow. While he himself does not fear death, he will not suffer for the amusement of the man who ruined his life. It goes against every fiber of his being, from the last remnants of Anakin Skywalker to the very core of the Sith Lord that he has become. He would not fight his son to the death. He would not kill his son.
So, instead, he walked through the halls of the Emperor's great Star Destroyer, the Executioner. He was a man who did not eat, did not sleep, and did not tire; Palpatine was resting, deep in the throes of the dreams of his conquests. He sat upon his jet-black throne, made from the painted bones of the Jedi who had fallen after the proclamation of Order Sixty-Six, head back and legs more forward than they should be when alert...it's too easy, he acknowledges. In the interest of silence, he will not activate his lightsaber until the weapon will position itself to go through Palpatine's head when he ignites the blade. Ignite it he does, and the ancient man dies instantly.
It's a quicker and cleaner death than the Emperor deserved, for all the suffering that he'd caused throughout the galaxy. As much as Vader would have liked to have made his master suffer, he cannot deny that his approach was the best; now there is no chance for Darth Sidious to rise again and torment the galaxy with his presence. Though he has never believed that it will be enough to atone for his sins, Vader accepted his choice.
Luke. He called out with the Force, connecting his son's mind to his own, and that is when he knows his son understands. It is done.
Father? What do you mean?
The Emperor is dead, by my hand. He intended to have me kill you.
He can feel his son's confusion, but cannot bring himself to respond to it.
Until we meet again, if such a thing ever comes to pass, I will remain in solitude on your mother's home world. It will be springtime there, and she always did love the flowers that it brought.
My mother? Mine and Leia's?
Yes, Luke. Her name was Padmé Amidala...she was the greatest, kindest, most selfless person I have ever known. She was the love of my life, the one that I adored. I was a fool, however. I wanted the power to protect her, but it only hurt her. All I wanted was to keep her safe, and she died because of it. Visit me, if you can find me, but come only by yourself or with your sister. Knowledge of my survival must be kept to the two of you, my children...of course, telling Leia about your mother will no doubt reveal my location. Until such a time as you come to me in person, I will beg that you leave me to my solitude and reflection.
Yes, father. I understand.
Their connection is severed, and Darth Vader enjoys the solitude for once in his life. There is nothing now...nothing at all. Nothing to prevent the years of unshed tears to flow freely down his burn-scarred face. Nothing to stop him from crying out, as he flies towards Naboo, in grief and pain and regret that he's allowed to fester for more than two decades. As he enters the planet's air space unnoticed, thanks to the power of the Force that he holds within himself, he flies to the one place that he knows he will not be noticed: the island-palace where they fell in love.
Or, at least, he thought that he wouldn't be noticed. The royal family was there, waiting for him, and Vader knew that it is time for more penance and repentance. He explained his intentions and his circumstances, even going so far as to reveal his true identity to them.
"But that must remain a secret." He demands. "Anakin Skywalker is twenty years dead, and my intention is for Darth Vader to do the same. This place is my self-imposed exile, my place of meditation, and where my fate will be decided. Though I would go home, to Tatooine, it is no longer my world. My home now lies with my heart, with Padmé."
They gave him leave to stay and do as he will, so long as he harmed no citizens of the planet...not that he would have done so. They were Padmé's people, her lifeblood, those she had served and who had served her. That made them his people as well, and he would protect them if they ever needed it.
It was two years before Luke came to see him, with Leia in tow. The Sith Lord sat on the beach, with his back to his children, staring out into the vast expanse of water that lies before him.
"When I first came to Naboo, after being freed from slavery, I was nine. My home is one that you know well, Luke. It was Tatooine, where water is virtually nonexistent...I was amazed that there could be so much water on a planet. In some respects, I still am."
While Luke was polite, listening to his father's tale, Leia chose to instead be vicious. "What's your point, Lord Vader? Stories of your past to make us feel sorry for you?"
He didn't look back, only sighing. "You remind me of your mother, Leia. Almost too much. You look like her and talk like her, with the same spirit in you. It's what drew me to love her, and I'm glad to see that it wasn't driven out of you by your upbringing on Alderaan."
"What's that supposed to mean?" The vehement violence in her voice isn't bothered to be veiled.
"I mean that I am sorry for you. For failing you as a father, and as a parent. It is my fault that you were separated, one to live the father's destiny while the other lived the mother's. It is too late for any apology to be meaningful, but I am still sorry for what my lack of presence in your lives has done to you."
She calmed down, to a degree, but the anger is still waiting to burst forth.
"This planet would have been yours to rule as monarchs, you know. Your mother was not just the ambassador and Senator during the time of the Republic, but also the Queen of Naboo. I saved this planet from the Separatist attack on it, more than thirty years ago, as no more than a child...and, ten years later, I came here to protect her after multiple assassination attempts were made on her life. Our love was forbidden by the Jedi training, and by her duty as a Senator, but neither of us cared. We left eventually, for Tatooine, in an attempt to save my mother's life. I had a premonition that she would die, and wanted desperately to change her fate...only for her to die in my arms. Your mother was the only one to comfort me, or who could. She was buried outside of the home you were raised in, Luke. Did you know that it was your grandmother's grave?"
His silence is all the answer that his father needs.
"Afterwards, we returned to Coruscant. I began to have more dreams, visions of a future in which your mother died. I did not wnat to live a life without her, and knew that I needed to be stronger than any Jedi before me in order to keep her safe. That was when I turned to the Dark Side...or, rather, I began to. Little by little, it consumed me. My fear became one that was not for my beloved Padmé or the life that grew inside of her, but that I would never be strong enough to save and protect her. That she would die no matter what I did to try preventing it."
He hears Luke's metal hand curl into a fist, because the young man knows what's coming. He can sense it in the Force, and in his father's voice, and with all the other thousands of minute clues that give it away.
"Her death was my fault. I became so consumed with power that I lost sight of the things which were most important to me, and I even attacked her in anger when I falsely believed that she had betrayed me...that was on Mustafar. Obi-Wan Kenobi, my former teacher and mentor, struck me down in the battle that followed. He severed both of my legs and my remaining arm, and left me to die in the volcanic flames. Sometimes, I wish that I had. It would have prevented these many long years of suffering, of outrageous violence and brutality. As my body was reconstructed with metal and machinery, then placed inside of this armor in order to keep me alive, I felt your births. Shortly after, I felt Padmé slip into the netherworld of the Force...my rage was powerful, and my hatred raw. I destroyed an entire star system with no more than my will and the Force, in anguish, though it took a month to destroy each of the five planets and another five altogether to obliterate its sun."
Darth Vader stood to his full, imposing height, turning to face his children. For the first time since the original Death Star, or perhaps Bespin, the remainder of the Skywalker family is together in one place. It is only then that Vader noticed a faint outline of blue, and he reached his hand out to grasp onto the lingering soul; deep down, he instinctively knew who it was that had been there this whole time, listening to him...but, all the same, he needs confirmation. Luke pulled the Force surrounding the ghost as well, and a face is revealed that Darth Vader had not expected to see again before his death.
"Padmé." The name is short, breathless, whispered in disbelief.
"Oh, Anakin..." She runs to him, wrapping her ghostly hands around his form while he does the same. "I knew there was still good left inside of you."
"Not in Anakin Skywalker." He intones, correcting his wife. "Anakin was a brash boy who desired power over all else. The good resides now in Darth Vader, and I hope that these years have been enough for my penance."
"You fool." She chides him. "You've been keeping yourself alive by using the Force, haven't you? Specifically for this meeting, when you know you're running out of time?"
The confirmation makes the children's heads spin.
"You're a fool, Anakin. A great, big, lovable fool."
"I know, Anakin. I know."
Ever so slowly, Darth Vader's consciousness began to fade. Before he could be wholly consumed, he gave his children two last directives: first among them was to ensure that he was buried in a pit of sand, and yet beside Padmé...though he may have remained on Naboo for long enough to realize that it would only ever be Padmé's home, that did not mean that he couldn't take his own small piece of it with him.
Secondly, he told them, they were to ensure that the life of the New Republic would prosper under them. To make a galaxy where another "Chancellor" Palpatine could ever be born.
That's all the time he had before his life left him, expiring more quickly than he might have thought. It was strangely painless for him, but perhaps he had his reasons for ignoring the pain. Darth Vader died, yes, but another man had returned in his place. Anakin Skywalker lives again, for a few short moments, before uniting with the Force.
"I love you both." Padmé said to her children. "And I am so very proud of you for all that you've accomplished. I wish I could stay for longer, but I don't have much time left in this form right now...and your father is waiting. I'll see you one day, but make sure that day isn't for a very long time!"
She disappeared into the light, but for a second in the image of peace they can see their father as he once was: young and handsome, with a scar across the edge of skin around his right eye that gave him a fierce sort of depth. He gave his children a wave and a soft smile, mouthing, "you can do it," before he is gone just as quickly as his beloved wife.
Were he corporeal anymore, perhaps he would have remarked upon how much he enjoyed the sweet release that came with the ending of his life.