i think the most boring thing you can do to padmé & anakin's relationship is to try to make it healthy and healing and the thing that could have Saved them.
when it's the thing that broke them.
they're both using each other as an escape from their lives & responsibilities. the relationship is a sort of fairy tale romance they both dream up. for padmé it's the risk of forbidden romance, the excitement of a jedi wanting to break their vows for her. it's an extremely common fantasy that a jedi might pick you over their vows and loyalty to the order and for her it actually happened. a very beautiful and passionate young man wanted her and wanted to give her love. she chose to soak it up & hold on tight to enjoy the ride while it lasted.
anakin needed somewhere to put all his love. he always has. with his childhood he needs to hold things in his hands, to be given unconditional love and told that the person he cares about won't leave, no matter what. he was on the cusp of knighthood, entering adulthood, he wanted to rebel in the biggest way he could. to say "look! i can do the thing you say is dangerous without falling! because i'm strong enough and better than my peers!" he wanted to win. to show that he could do what no one else apparently could. (what other impulse is supposed to come from a kid being told he's the chosen one and special beyond the rest?) the connection to his mother had been cut long ago, and his closest connections were all very repressed and distant. his teachers weren't offering unrestrained affection, they were teaching him. and his peers, the other padawans, they didn't like him for being different. for coming late, for having a life experience they could never understand. for being more powerful than them, and naturally skilled. he didn't get companionship from them either. he received scorn or suspicion, more than anything. but padmé, when he offered her affection, gave it back to him. and he instantly clung to that, starved for it.
they both use each other because they're beautiful ideals of partners to each other. the attraction, initially, is shallow. and then gets shot into the stratosphere by the way anakin's desperation to love and be loved in return turns things serious & unbalanced & attached.
just look at the way we see their relationship play out in the films. they don't mutually confess & kiss & give in until they're both about to die in a gladiator arena. then they both survive their brushes with death, anakin loses an arm, and a war begins. they marry as a means of clinging to each other and searching for something they can control in a universe that has suddenly robbed them both of all control.
then the relationship that follows is one interspersed by long gaps between seeing each other at all. they don't spend quality time together, never deal with the heavy stuff like having to manage each other's personality traits that clash with their own. they only get brief moments here and there, where the fantasy can still hold. anakin doesn't even learn padmé is pregnant until she is almost to term, because the war has kept them apart for so long. and while she tries to be realistic in her fears about their secret, he reassures her of the fantasy instead.
they chat and smile together in her apartment as they imagine an impossible future where their secret won't come crashing down and tear everything apart in a matter of weeks, with the birth. they talk like everything is and will be fine, as long as they just love each other. it sounds forced and strange, because it is. they're both clinging to the very thin veneer of normalcy in a relationship that is about to splinter apart, because the lie is about to destroy them both.
and then when the fantasy is finally irrevocably shattered by anakin's fall, and the republic's fall, padmé cries and begs and tells him she doesn't recognise him. because she doesn't. regardless of his reasons and justifications, he's torn down the the image he projected of her lovely secret jedi husband. she can no longer pretend it's real. and as she rejects him, she tears down her own false image in his eyes. she is no longer the perfect receptacle for all of his love, accepting him unconditionally. she's leaving. abandoning him. and so the way he reacts, snapping and hurting her, is inevitable.
their relationship has festered in the dark and behind false faces and the truth is anakin never needed someone to accept him unconditionally. he didn't need someone to simply accept the slaughter of the tuskens and keep it hidden. he needed someone to bring him to task. to challenge him and his actions, when they strayed so far.
and padmé didn't need a partner or a relationship that she could and would put before her morals and calling. that would cause her to break laws and hide terrible secrets. she entered one, and let it turn her into someone who would plead with a murderer to come away with her, ready to give up the fight against the empire for him, even at his worst.
mustafar, in essence, was fated from the moment they kissed on geonosis. it could never have really gone any other way.