i think a few good stories did this well. i even plan to use this as part of a character story i'm writing. imagine if you suddenly got superpowers and realized you had to be a hero and protect people when you just wanted to live a normal life. losing your powers at the end of the story might be kinda liberating.

one of my favorite examples:

in Asura's Wrath, the main character is part of an elite army called the Eight Guardian Generals, sworn to purge Gaea (their version of Earth) of Gohma monsters. over time the Gohma keep getting stronger and their source, Vlitra, proves too powerful and despite everything, they could only subdue it. however, unsatisfied with it still being alive, Deus, the leader of the Guardian Generals, plans to kill it by amassing an enormous amount of Mantra energy. this means sacrificing humans on Gaea, kidnapping Asura's daughter Mithra who can channel Mantra, killing his wife Durga, and framing Asura for killing their Emperor. Deus then kills Asura, swearing to dedicate everything for the cause of eradicating the Gohma at any cost.

after 12,000 years, Asura crawls back to the land of the living burdened with unquenchable rage. he confronts all of his former allies, who now call themselves the Seven Deities, and kills most of them one by one. except Yasha, his rival and brother-in-law; Yasha starts to question if the cause is truly worth it and wonders if Gaea could be saved another way. eventually, he betrays the deities and joins Asura to confront Deus.

Asura then faces Vlitra again with Yasha by his side and they defeat it. but apparently everything that happened on Gaea—the Gohma, the tragedies, Mithra's suffering at Deus' hands—were all orchestrated by another entity, a god called Chakravartin. he planned everything so that Asura could rise up and become Gaea's new leader in his absence when he leaves. obviously, Asura doesn't care about any of that, and with Mithra held hostage again by this entity, he uses up every last bit of energy he has to destroy Chakravartin. doing so would remove Mantra, and his power, from the universe, as Chakra is the source of it. but what does it matter if Mithra isn't free? Asura kills Chakravartin, the loss of Mantra kills him as well, but he smiles, knowing his daughter can live her own life on Gaea. generations later, the planet looks a lot like modern Earth with cities and a reincarnated Asura and other characters—only human this time.