The thing is, Kael isn't obligated to feel the same way she does (as in, needing revenge or just being hung up on it in general)– but for some reason Hes is acting like the fact he doesn't is somehow a betrayal to her and everything she has done so far, like he is somehow "ungrateful" :/
But it's true that he is ungrateful, if he doesn't want to dethrone her then explain it not stopping it like that after all Hes has done for him. If Hes doesn't do that thing then he will dead by now. So he should feel grateful because he doesn't die and have Hes whose love him
Yes kael can be forgiven towards them thats true, but Hess has all right to want to just get away from all three them. Remember she has no one in this world (you can say kael but he live in this world his whole life is here) who will she turn to if something happens no one.
That is not how being grateful for someone works. Being grateful is not the same as owing them something; Kael can (and is) plenty grateful, but that does not imply he needs to agree with Hestia on everything. Everyone has free will, and you cannot force feelings onto someone; in this case, no matter how much he loves and appreciates Hestia, that does not equate to Kael needing revenge the same way she does.
If you hold the fact Hestia saved him over his head, that's just plain manipulative and lacking in empathy. If Kael were to act solely on this basis nothing in their relationship would ever be genuine.
Hestia has all the right, correct, but her current obsession with this is unhealthy. She is not really living her life as much as she is "surviving so that she can enact her plan." It's obstructing her judgement in all sorts of ways. The fact she comes from another world as is, in that sense, alone, is all the more traumatic for her– but that just means she needs to find new meaning in what she currently has, because she can absolutely lead a cherished life here if she tries. Just like how she took care of Kael by making him do different things in order to see how much life has to offer, she needs to allow Kael to do the same for her and allow *herself* to find that joy in multiple facets of her life.
The revenge can come a bit later, or with a little less involvement from her. It won't make it any less meaningful. She just needs to live her life past that resentment.
When u someone hurt the person u love, even if the love one forgives them doesn't mean you will. Imagine seeing this person driven to the brink of death and then they say they forgive the person it will hurt you so I understand hess. Jumping to death is extreme but want to escape especially if u feel u dont belong she has a right to want nothing to with him or them