The good was in him.
Anakin Skywalker's dreams of fixing the galaxy eventually led him into turning his Jedi ways into an allegiance with the Sith. At least on the surface. It was one of the most painful decisions he ever had to make, except the need to forsake the love of his life. The fact is, even when he became the Sith lord Darth Vader, Anakin never lost his way. He began as an idealistic dreamer, and that was how he ended his days.
Supreme Chancellor and later Emperor Palpatine came to him in secret. It was Padme who came to him openly. Padme, the love of his life. The only one who understood his dreams. His life had put him on the path to the Force, but Anakin's vision of the future embraced more practical means. When Padme became a senator of Naboo, he asked her what it would take to have his home planet of Tatooine similarly represented. When she told him that it took an established infrastructure and a duly elected representative, he abandoned the idea, knowing that the corrupt Hutt mainstream would have rigged the election, and he had little interest in compromising more than necessary. Bargaining with the lives of strangers, even friends, was one thing. Bargaining with family? He couldn't do that.
So he listened to what Palpatine had to say, went along with the transition from Republic to Empire, watched and even participated in the destruction of the Jedi Order. Padme's resistance fighters included the man who would adopt Anakin's daughter with her, Bail Organa. Organa was reasonable. Although Alderaan was a peaceful world, it knew better than others the price of peace. Although it tried to live by its ideals, this was a world familiar with compromise. Every chance he got, Anakin would visit Alderaan, he and Padme together. This was the reason Organa received custody of Anakin's daughter. When he became Vader, it no longer mattered where she was. Padme was dead. He could no longer retreat to safety. But he kept Alderaan in his heart.
Alderaan led the cause for the Rebellion, the successor to Padme's resistance. Anakin knew this, of course. Everyone knew it. The Empire simply lacked the ability to confirm it, and without proof, even the cowed members of the other worlds wouldn't stand for it. That was the whole reason the regional governors had to remain in place until the Death Star could be completed. This worked to Anakin's advantage. He could have easily betrayed Alderaan in an instant. The only reason Palpatine didn't have him do it was because the Emperor overlooked the threat. He didn't find it significant. The only threat he understood was connected with the Force, and he had Anakin at his side now, as Vader. Aside from the two of them, there were no existing viable practitioners remaining, and none who would be rising anytime soon.
Within two generations, that would certainly no longer be a problem. Anakin was aware that Palpatine had been alive for nearly a millennium. He wondered if the apparatus that had completed his transformation into Vader would give him a similarly elongated life. He didn't want to count on it. He knew that he had a daughter, and he knew about her twin brother. Palpatine knew about them, too, and only thought about them as possible replacements for Anakin. Such was his concern about even his most trusted allies. Anakin wondered if things had gone differently, if he hadn't lost his nerve, if that fight with Obi-Wan had never happened...But he's willingly walked into that. He'd foreseen it. It was a necessary sacrifice. Even Palpatine hadn't seen it coming. But Anakin had known about it all his life.
When Yoda sensed fear in him, it wasn't for his mother. It was for himself.
He always knew what he had to do. He didn't expect to fall in love with Padme, but he knew from the moment he met her that she was the other half of his vision. Without her it was incomplete. He was incomplete. So he endured. He nurtured the Rebellion, watched it grow. When his daughter came into his grasp, he pretended he didn't know her. She reminded him too much of Padme. His son was different. He was like the young man Anakin might have been, if he'd never received that vision. Both children were necessary for the Rebellion to succeed, echoes of their parents. Only this time, the sacrifice would be complete. Anakin could finally allow himself to endure what he had caused so many others before. The noble death.
The only one who knew any of this was Obi-Wan. He shared the vision with his Jedi brother almost from the start. It didn't hurt that another had experienced the vision before him, Qui-Gon Jinn, who must have told Obi-Wan about it before he died. So they both knew what had to happen. And what Obi-Wan himself would have to sacrifice.
They fought together during the Clone Wars. At the end, they fought each other. And what had to happen happened. What followed was Obi-Wan going into exile, watching over the son and being the last remaining hero whom the daughter could call on, years later. And then that sacrifice came full circle, too. No one else knew.
Anakin became hunted for the first time. He was heartbroken. But he endured. What else could he do? He watched as his children led the Rebellion to upset after upset. Until his son stood between Anakin and Palpatine. Nearly became another sacrifice. But then, Anakin was finally ready to make his move. He finally put an end to Palpatine, and along with the rest of the Rebellion, the whole Empire. At last.
But at a price. His life. Finally. But it was always going to end that way. He only regretted that his redemption came too late. He couldn't tell his son, his daughter, the truth. In some ways, he didn't have to. That was why he died a happy man. A good man.
Finally reunited with the love of his life.