After reading the manga up to this point I've got a few ideas about how this situation is coming together (or falling apart).
Considering the fact the twin goddesses have always been full blood spirits, with no real understanding of how humans think or function, like their lovable and somewhat ditsy little sister. These doting imouto-cons are highly interested in anything related to goings on with her and their darling little niece. If they are just as smitten by Ori and Ellen as Rovel, they may be just as much a cause for "disappointment" (in Ellen's opinion) as Rovel when his brain turns to mush from her cuteness😍. Now consider how they would react when precious little sister's potential love rival is submitting a vow to forsake all others while visibly addled by the presence of little sister's spouse. I think the judgement Aria received was mild considering Origin was flustered to the point of considering the most appropriate means of destroying the planet when Aria reached for his hand. The sister that responded to Ellen's prayer seemed to have Origin's easy going 'no worries' like mannerism so they may be just as ditsy too.
Watching Ellen's father he seems to have been a bit of a introvert his whole life so he may have never really related to anyone other then Origin. He considered people to be pretentious and obnoxious. He spent all is time in excelling in his specialties of warfare, and now he has been faced with a situation he can't just eliminate with a sweep of his blade, or spirit magic. He was often pursued by the opposite sex, and may have developed his back off thot attitude at a early age. It's likely he may consider the possibility Ellen might be used as hostage to manipulate him, Origin, or even the twin goddesses in a situation like what occurred 200 years prior. (Think the terrorist hostage taker threatening and in some nasty cases actually following through with the threat to kill a hostage every 5 minutes till the his demands are met) And that's considering they don't exploit her personal elemental abilities, or use a political marriage arrangement to form a favorable relationship with the spirit realm. Can you really blame him for being ready to wage war on any perceived threat? He was nearly crushed by his emotions when he glomped Ellen last chapter. His thrash the fish about to unset the hook technique with the girls his legendary status snags may be painful to watch, but he has little patience left after being pushed deep into a corner.
As much as Ellen may be a genius, her past was more then likely that of a bookish lab nerd. She's brilliant and less oblivious then a child, but a geek's not going to relate to people the same as normies. She can pick up on the likely consequences when her father blew up, and threatened to forsake the earthbound branch of the family because of Aria's treachery, that Aria would be identified as a threat to the country's strongest military power provider household's stability. Aria would be in the same situation as a hound dog that repeatedly spooks the master's game at precisely the worst moments, if the hunter spots a fresh trail and a successful hunt hinges on a distasteful decision, it'd be likely the dog wouldn't make it out of the woods. Ellen wanted to convey that message to Aria, but she has a bit of a odd manner of interacting with people and comes across a bit harsh at times. But I can understand the "if you try to steal my father I'll wreck you homewrecker" sentiment also. Sometimes a girl has to firmly stake her claim you know.
Still not sure about Aria. She may have been a Bakarina-ish girl that earnestly went about her duties as a barmaid and drew the hearts of people around her. She may have been the type that was aware of her effects on men, and used her charm and assets to get more sales and tips without any nefarious motives. She may be a more reserved and streetwise version of the orc princess Sauvel was married to while she acted as his mistress. I can't say if she genuinely loved him or if he was a means to upgrade her lifestyle and status. If she does love him she could have still been rolling the stories of the legendary hero in her head like most of the people in the country. I'm sure a large portion of the womenfolk in the country had romantic fantasies of the hero coming and whisking them away. If Aria had those fairytail like thoughts filling her mind before her relationship with Sauvel, it could add to the effect of actually meeting the hero in person. Even if she wasn't charmed by his spirit aspects, overcoming irrational celebrity hero-worship awe, and desire would likely have many a girl swooning for a while. 😍
Just my take on things. What do you think?