How exactly will one misapply responsibility?

But, would this not lead to the self-proclaimed guilty person carrying the blame through life, seeking to make things right until they deserve forgiveness and suffer in the process thinking about what they could have done differently, all while an opportunity good enough might take some time to show up. Leaving them in this uneasy mental state.
A example for this may be the lore underlying the character of 'Peter Parker' from 'Spider-Man' where Peter's uncle dies in a attempt to stop a armed thief who is the same thief Peter let go earlier while he ran away stealing from somebody Peter was betrayed by minutes ago.Peter allowed the thief a easy escape despite having all the tools to stop him.
Peter blames himself, and seeks revenge and when he does get it, its not enough for him to be forgiven.
He continues helping people, but deep in heart he carries the burden for the one thing he could've done right, all while he never gets an opportunity big enough such that he could forgive himself.
Now, what should he do so that he is able to afford forgiveness? and is him forgiving himself is just him doing what he thinks his uncle would want him to be doing at the moment. But I can't think of something that his uncle would've wanted him to do which would be different than what he would want if he was still alive and the thief incident never happened. So in conclusion Peter has to just forgive himself and move on doing the things his uncle wanted him to do beforehand because no event big enough could allow him to redeem himself in his eyes.
My understanding of forgiveness comes from this video right here: https://www.youtube.com/watch?v=7hzA9jrmk7s

Yes.