You're pretty much only bringing up things that aren't really related to Joel's murder. She didn't get ptsd from that, that's not a consequence of her revenge. Same with the seraphites and so on. And while she is hesitant to talk about Joel it didn't exactly feel like it weighs too much on her conscience....Killing Joel didn't solve her problems but it hardly created any social or mental issues for her. If the intention was that she swears off revenge because off the toll it takes on her mentally and socially they imo failed there.
Your original comment was that Abby was "fine" after killing Joel. She wasn't fine, she was miserable before she killed him and after she killed him she was substantially more miserable than that, and even before killing him a lot of her problems were the result of her obsession with killing him. When she finally did it, her relationships with the people she loved were permanently scarred and all she felt was self-loathing. All she ended up with is more nightmares and friends that couldn't look at her the same way again.
I think you're saying "consequence", when what you actually mean to say you want her to experience is "punishment". And for some reason, you're framing "punishment" as needing to be a new effect on her life, which it doesn't have to be. Her murder of Joel had a escalating effect on everything wrong with her life. Joel's death weighs on her because not only was it excessively brutal for her, but it also didn't solve her problem of having unending nightmares about her dad, which was the whole reason why she did it, and BECAUSE it was so brutal, this means she butchered a man for nothing and she is contending with what kind of monster that makes her. She hates herself for it. Her killing Joel made her life materially worse. But I think what you want to say is that it didn't make it "worse enough" and my response to that is....that's not how this storytelling works.
The reason she isn't being directly punished for the killing Joel is because Joel isn't special to Abby except as a personal demon, and once she exorcises him and all it does is make her life worse, she changes. To her, Joel was a landmark mistake, and in making that mistake and sinking to the lowest she felt about herself...but due to sinking that low, she decided she'd rather improve her life instead. And that then lead to the plot of the game where endeavors to save Yara and Lev, which itself leads to all sorts of consequences for every character.
In other words, she wouldn't have made the changes she did if her killing Joel didn't make her fucking hate herself so much that she'd do anything to stop feeling what she's feeling.
Hell, she was still eager to torture some seraphites when arriving at the FOB.
Okay, this one is just wrong. She does the WLF soldier thing of dehumanizing the Seraphites because that is just the culture of war. Soldiers do that as routine mental conditioning because they want to have as little empathy for their enemy as possible. And it frequently works, but for those who are empathic people, it tends to stop working when confronting the reality of a situation. She may say that she wants to torture the Seraphites who just jumped and nearly killed them as a display of viciousness, but when she actually arrives at the FOB and
sees people who have been tortured by Isaac, she's clearly uncomfortable. Out in the field? "Yeah, fuck the Scars, I'd love to torture some myself" Okay Abby, here's Isaac's torture hotel, are you having fun yet? "*tense silence*"
And honestly, if anything, it's a bit of a running theme with her that she is either in denial or dishonest about how she feels until she is actually forced to reckon with the harsh reality of whatever she's saying. She'll agree with Manny that Seraphite kids deserved to be shot for being enemies, but one afternoon with Lev has her tiredly saying "They're just kids..." to Owen and reflecting how fucked up being a WLF soldier is. She'll tell Owen that their night together didn't mean anything and tries to force him and Mel together, but she breaks down so much she vomits out of sickness when she finds his dead body and realizes the love of her life is gone. And she'll brush off her torture-murder of Joel as justified and projects judgement from others onto others, because she's actually judging herself.
To understand her as a character, you can't just take what she says at face value, because she talks a lot of bullshit, either intentionally or otherwise. Her typical emotional state is "thisisfine.jpg" You have to decode her through her body language, her actions, her relationships, etc to get at her true self.
And this leads back to Ellie's own moral quantity. Abby committed "that kind of murder" and walked away pretty fine if it hadn't been for Ellie. This turns the whole message on it's head for me when it's presented as Ellie being on the abyss while Abby already showed the life beyond that abyss, and that life actually isn't so bad.
This is a strange thing to say. There is no abyss, atleast not the way you're thinking of it. Or, alternatively, there is, but you're trying to be dismissive of Abby's feelings.
What you basically seem to be saying is that if Ellie had killed Abby at the end, then she couldn't equally 'ridden off into the sunset' like Abby apparently did in your mind after killing Joel? Yes she could. She'd still have to deal with her ruined relationships and the guilt that would come from the fact that she murdered a woman who was just brutalized and helpless right next to a child she see loved Abby as much as Ellie loved Joel. And it wouldn't have stopped the nightmares, it wouldn't have mitigated the guilt over never reconciling with Joel, it wouldn't have fixed Dina or Tommy, and it wouldn't have done any good to anyone. And the only reason that Ellie is undertaking this journey is because she wants to all those things to stop, and it would just get worse. But those are all literally the same problems Abby had to contend with - ruined relationships, depression, lack of catharsis, etc.
And apparently that's fine? Because that's still less than what Abby deserved? No. The journey of both of these women is to move beyond a life of hatred because that hatred is toxic and kills everything they love. Abby had to kill Joel to realize that killing Joel does nothing for her. Ellie, meanwhile, was able to realize this before she killed Abby. But both these women were already in the abyss long before they held the life of their hated enemy in their hands. Them being beyond the abyss is when they put the hatred aside.