Like, have you played the game?
Played through it twice to get the Platinum.
Ellie's arc is that she realizes too late what her revenge cost her, despite everyone but Tommy telling her to stop it
Jesse never tells her to stop her revenge, in fact he only appears in the game later to HELP her get that revenge. Only wavering when he learns of Dina's Pregnancy in which Ellie suggests he stays and takes care of her and takes her home. Dina doesn't ask Ellie to stop until the end of the game to try and prevent her from going to Santa Barbara. Even when she reveals she's pregnant and Ellie conflicts with the need to take her back home Dina says she doesn't have too. Dina encourages Ellie to keep going, even staying in the Theater to study maps and monitor radio communication to help Ellie track people down. She gets sicker later on, but that doesn't really make her discourage Ellie from anything. Jesse is the only one who freaks out a bit about it and even then Dina doesn't want to leave Seattle.
That decision happens after Ellie kills Mel, and Tommy is back with the group. Killing Mel is the only thing that calls Ellie back from whatever revenge mission she's on when Jesse and Tommy both insist it's time to stop. However even that choice is taken away from Ellie with Abby shows up anyway.
Ellie doesn't really have any character moments in the game and that's the problem. If she is supposed to be consumed by revenge, then she would fight against going back, she wouldn't banter with Dina like two kids on a Seattle Date Tour during Day 1. She would be focused on the mission, she would be consumed by it. That was the pint wasn't it? We are supposed to believe that she is consumed by the desire for vengeance? Yet the game literally never shows us any consequence of her morality going out the window for the sake of this revenge. She's not consumed by shit, she's just going through the motions because we need a game to happen.
There are several times in the early Abby levels where this is brought up, especially in the strained relationship between Mel (who thinks Abby went too far) and Abby
There are times when Abby asks her friends for reassurance that killing Joel was what he deserved. Abby asks Mel this directly to which Mel replies, "I think he deserved worse." Manny is also encouraging. It's never brought up with Owen because Owen's going through his own thing, and it's never brought up with Yara or Mel. Outside of a few throw away lines early in Abby's section it's never brought up as a part of Abby's character. She never reflects on what she did to Joel, there is never an emotional debate that we ever see with her.
As for the decision to help Yara and Lev, it's never suggested that Abby goes back for them because of any sort of sorrow, regret, or desire for redemption. She feels two things, one they were just kids, and that they helped her escape when they didn't have to. So she goes back out of obligation from that regard. If it's meant to be a redemption of Abby for Joel's death, the story and the game never make any suggestion towards this.
The narrative is very polarizing on purpose. Ellie deals only in selfish death, and Abby is the hero who saves children and plays with dogs.
The entire point of the game is that revenge is cyclical and that eye for an eye will make the whole world go blind, to borrow a phrase.
I get what the game is trying to be about. My point is that it fails to deliver on what it's trying to do because it's written terribly.
Ellie, at that point, decides that she has to avenge Jessie too, something that consumes both her and Tommy.
Jesse is never brought up again after he gets shot. Tommy also does a 180, from being willing to drop it in the Theater, to being hungry and all consumed by revenge back home months and months later. Which doesn't make sense, unless he is simply mad from taking a bullet to the back of the head. (Which there is no fucking way he should have survived that, when you consider that nobody would have been able to help him with a fucking bullet to the head in any timely manner. Considering the only people alive to help, where beaten to shit back stage. Let alone the travel time from Washington to Wyoming in which someone would have been willing and able to help him.)
Mel wasn't innocent either. She would have survived the encounter with Ellie if she had not attacked Ellie in the first place. Both her and Owen, who at that point where basically done with Abby, tried to fight back against Ellie and got killed for it. Which asks another question. Ellie was supposed to be fully consumed by revenge still at this point, so why the hesitation? The moment Owen struggled against her, a woman blinded by revenge should have just shot them both and left. Again this shows that despite Naughty Dog trying to tell us that Ellie is bound and consumed by her revenge, they do a piss poor job of imparting that motivation upon Ellie at any point in the story.
Take a look at the box art. At no point does Ellie look that angry or consumed by her vengeance in the entire game. At every moment Ellie, hesitates. As you said, with Nora, with Owen and Mel, outside of NPC's during gameplay, Ellie doesn't purposefully kill anyone important to the story at all.
But Abby does. Kills Joel no problem, kills Jesse no problem, shoots Tommy in the head (to kill him) no problem. Lev doesn't try to stop her doing any of that. It's only when it comes to Dina, do the writers use Lev to pull her back as if that's the noble higher ground when she just shot and killed two of Ellie's friends in an instant without hesitation. And if Lev had been 20 seconds behind, she would have slit Dina's throat without a blink.
It's funny, Ellie hesitates at every kill, and Abby doesn't. Yet they want you to feel sorry and empathetic towards Abby. That's bad writing full stop.