Why does Jon Connington dislike Elia so much? She died in such a tragic way, yet he never has a kind word for her, not even in front of her 'son.'
DISCLAIMER: I could have been concise, but as I was writing all this, I came to a lot of realizations, so apologies in advance.
It's a very passive hatred and I think it's because he's uber-closeted at a level that's breathtaking. Wholly, it's a coping mechanism of and against queerness and misogyny the way with him for that. He's a bag of self contradictories and doesn't have much regard for his own life out of a deep sense of failure to perform an ideal he layers on top of his extant political function as one of the Targs' protectors. I often think about that one poem where the speaker's like "I am not in love with you, I am in love with being in love" when I try to think about Jon Con.
Like Cersei, he eventually pedestalizes Rhaegar and even more so after his death. He's made him into a paragon of male virtue and human appeal so he could continue to feel his desires are not abnormal. While Cersei does it because it was like she was as close to the sort of power masculinized in that world and denied to woman (which is just as a "visceral" thing, to have agency), Jon Con does it to affirm his own "lacking" masculinity. He is not totally comfortable with his own sexuality nor the yearning since he still has to go out into the world and "be a man". Through Rhaegar he definitely can at least privately express/validate that yearning and feel like a man but also close to "men" without having to really address it consciously or exposing it. By not really confronting the layers of himself "all the way" or as much as he could, he re-relies on that patriarchal definition and field of "manliness". It's close to having one's cake and eating it, too. A compulsion that replaces real connection; but it he kinda transformed himself into an all feeling automaton in the process in order to fulfill the compulsion to "sacrifice" his life to something like a higher purpose. And Elia was not a person-person but a means to further Rhaegar.
A)
This is a society where:
there is an emphasis on obedience, maintaining the social hierarchy, and obligation to one's "lord" or the gods, and yes the Faith of the Seven (the fictional Catholicism) informs the model of masculinity in Westeros, esp through the Andal chivalry and courtliness; the express/prove/practice the "greatest" form of love to either a lover or the gods or one's lord is to completely sublimate oneself to the gods'/lord's rule and wellbeing...which kinda came on conflict with the whole warrior-takes-all thing until the emphasis on fighting for a specific lord but it's self contradictory in its rigidity
men who may love to read without also swinging swords/being good at that and aren't maesters/are not studying to be one are close to "unmanning" themselves. Let's sit with that. Maleness is proving to other men you have "strength" and having control over as many bodies as one can...doesn't really lend into exploring oneself or seeing things to appreciate in others or nature, and aristocratic maleness (the primary-only ones allowed to use warfare to acquire resources) is the ideal/only "human" that exists or matters. A man's very health is treated one and the same as his "manliness", sometimes literally (some research reveals that having a mistress showed a ruler's very virality and prostitutes were "necessary" for men to relieve their pressing "urges" without becoming violent and disrupting the "order"--[at least]15th to 19th centuries). This sort of context breeds very emotionally stunted men who can really/mostly only objectify people and compartmentalize others and their own emotions. It breeds a certain inflexibility in men that close down their means of really being aware of their own actions' consequences or caring beyond THE GOAL. You also must dehumanize women.
Every person in this society who does not or can't conform to the conscripts placed on them according has had to develop ways to both perform their social "duties" while coming to terms with the limits of said duties on how they can express themselves, find intimacy, access resources or amenities, accrue social respect, etc. For men, that is military achievements and violence to show you can get material objects and/or protect your lord's best interests. One thing about Jon is that he's always been hungry for "glory" like many other men and boys, to make his "name" mean something and gain that sort of "love". Problem with this sort of masculinity is that it cyclically generates an insecurity in men & boys and compels them to disregard most other types of male affection other than those which "coincidentally" serve the higher lord.
GRRM informed us that Jon was gay not-so subtly. Unlike Laenor or Renly or Loras or the Daeron prince Olenna avoided marrying, Jon hasn't had a real lover (someone he shared a life with) to even help to alleviate this compelled loneliness that goes beyond having a lover. And I don't mean people he's slept with, I mean a man invested in his well being, always having his back and prioritizing him the way very close companions or partners do. This maybe Jon's most safe way of experiencing lover's love and "love" himself.
B)
So another thing about him coming from this phenomenon is he seems to want to have real male companions & "love" them in other ways than just romantically. But even male platonic affection is pretty restrictive as much as we have Ned and Robert's friendship...which we see in the first book is unsteady and false with every realization that Ned has about Robert.
Making up for that kind of stunted platonic love, the sensual (diff from sexual) affection he has for men & Rhaegar works to maintain that sense of intimacy he craves. Once when Rhaegar visited his family's lands, Jon says Rhaegar's music/voice moved women to cry, and they seemed to connect to something he is aware of in himself (again, other than his sexual attraction to men), but the men around Rhaegar do not or won't and thus cannot even fathom or detect. A certain "appreciation" for beauty in life or the capacity to observe such, which is a sensual experience in of itself. That would be a wonder to see in a man; the beauty is and has to be under a guise of male domination. Loras and Renly, that Daeron prince and his lover, and Laenor x Joffrely/Qarl still must live in secret, as open as it was, but theirs was a different sort of "hiding" bc they don't hide themselves from themselves to the extent that Jon does. I think that it is very likely that present-day! nor past!Jon may not grab that chance of love and companionship because the covertness of the love like Renly/Laenor/Daeron can no longer compare to the imagined satisfaction or fulfillment of his obligation to Rhaegar OR/AND it would mean he'd have to re-adjust some ideas of masculinity he doesn't want to re-adjust, and like I mentioned I think this guy feels the need to just hold on to every scrap of conventional masculinity to feel normal.
The men like his father certainly cannot care about such a visceral thing that exists in these people that makes them feel connected to something more then themselves but also exactly like themselves; his dad was way more eager to talk about lands with Rhaegar and acquiring them to care. So perhaps Jon also saw in Rhaegar's known melancholy disposition who didn't quite fit Andal-Faith patriarchal conventions a fellow outsider. The single-mindedness I mentioned could come from his own unwillingness to really let Rhaegar be a normal guy.
He def always tried to put his yearning to use into a source of the single-minded devotion to his political function to Rhaegar and his family as a protector. Rhaegar was good with the sword, but the symbol we readers and the world then see him through his songs and his harp; Rhaegar is a figure of poetry and emotion that is socially divorced or posed counter to warfare, and he like Dany or Lyanna moves between the gender binaries of this world. Rhaegar became the lynchpin to Jon's own understanding of what a "man" is through Rhaegar being a sort of portal to this "thing" that really many humans across identities feel, this sensual love for life and anything that could psychologically move you (you can't really "escape" music and thus music has always been a very "easy" spiritual device to transmit emotion).
Even before Rhaegar's death, I think he felt very indebted to and psychologically dependent on Rhaegar's wellbeing, which he conflated with political "success" through a legacy now that the actual man is dead. Rhaegar has to mean something so his own dedication might be "real". Rhaegar's death and then his failure to even perform this "simple" duty towards Rhaegar only inflated this devotion to this sort of devotion.
Rhaegar's family (Elia and the kids) is only as valuable as what they do for Rhaegar-the-heir, Rhaegar-the-man.
C)
Jon does express that Elia's death was horrible (A Dance with Dragons - "The Lost Lord"):
but it's less about Elia's suffering and how her suffering is part of the larger loss he and many people saw that the Targs and esp Rhaegar had. Elia is not really much of a person so much as a vessel or device AND a part of a whole.
She also got to be with Rhaegar and experience many more aspects of inaccessible intimacy he feels he can never have. Be sexually and emotionally (even if not exactly romantic) intimate with him in all the ways Jon Con never could. AND IN "PUBLIC" in ways he could never even if Rhaegar ever returned his feelings.
And after all that, she can't do the one thing that she/women in general in this society are socially "obligated" to do (A Dance with Dragons - "Griffin Reborn"):
I think that part of how he dealt/deals with his unrequited AND unfulfilled (read: "impossible") affections for Rhaegar--AND/OR men/human love in general--is that this and most marriages have the function that would benefit Rhaegar in getting him heirs, and Jon himself can "benefit" or be useful to Rhaegar as his and his father's Hand or protector. An expression of that affection-devotion, a tweaking of the lady and her courtly knight/lover from courtly and chivalric romance, but gay, or really queer. Because his secret yearning runs parallel to his sexuality and his sexuality fuels that sensual. yearning, it's queer as all hell. But he's so baked into the masculinity train, he also still carries the sexism.
If Elia, who's allowed to receive Rhaegar in those desired forms, can't even do "this one thing right", it's like a slap in Jon's face at times because that small nest, this group of people bounded by "duty" and practicing affections (Elia, Rhaegar, all of Rhaegar's closest friends, himself, Rhaegar's children) that he convinced himself to adopt as his existential purpose, is created for the man he idolized, or centered around him. As what this system designs that to be, as when if you need anything done you need heirs, connections, etc.
We also know Rhaegar had some sort of private goal, and every companion he had may not have told them expressly what it was but each more than likely wanted to anything they could to help him nonetheless perform it, which entails self sacrifice.