it makes sense to me that maggie is the one capable of saying something cutting to rust, if only by being the only woman in his life who isn't dead. the whole crux of the conflict, in terms of the state of the soul of true detective, is rust and marty's denial that all men's weakness, sadism, beliefs, mistakes disproportionately destroys the lives of women and children, and the men who do it get to just keep truckin, sometimes with guilt heaped on. they just get away with it over and over and it kills women and girls. I think of rust's, "she sounds sad, marty, like a person on their last legs" about dora after visiting the bunny ranch. how dora was predated on by her father ("why wouldn't a father bathe his child?"), ended up with charlie lang, and was then marked as a target because charlie showed her naked pictures to his cellmate who he hated.
marty's whole hang up is just a classic cop one. he's the good guy and he hunts the bad guys. rust doesn't think he's the good guy, he's just another bad guy hunting bad guys, but that's still denial. when he passes a tide of hallow rationalizations to maggie, they suddenly sound like exactly what they are. normally rust has been monologuing to male audiences -- papania, marty -- who balk and seem defensive or quietly suspicious, but when maggie is the audience you realize rust actually sounds exactly like marty giving his stupid "you gotta decompress" schtick. she's not hung up on any of his actual ideas, doesn't take a single one seriously, because it turns out they're a baby blanket. in rust's phrasing, they're just the encouragement of illusion so he can get through his reality. that scene coming so soon after rust saying, "when I think of my daughter, what she was spared." he just can't do it yet. despite all his efforts, he just can't look at anything head on, not until the end, when he's in that syrupy blackness experiencing his loved ones. he only edges up to the truth, keeping himself mostly at arms length. he gets right on top of it in that same monologue, "she spared me the sin of being a father." the death of women in girls in this season are redemptive; the childress' seem to use them as some kind of baptism. when they're not around to destroy, the men who destroy them are spared of being the men who destroy them.
marty is always under the impression his intentions are good. "was that a down payment?" and marty chews him out for "joking" about his moment of decency, but it was absolutely a down payment. rust clocked it correctly, most of the reason marty was mad was because he was attracted to beth, and he started blustering some rhetoric and then gives beth a twenty, hissing out a white hot, "do something else," like an accusation. but marty goes through all the motions of a hero, so to beth he looks like one. he slaps his daughter and calls her a slut for doing the kinds of things he does with women. he beats on the men she was with so he can feel like a Father and a Hero then vomits in front of his car because it was all just clumsy violence and cowardice. rust knows he isn't doing any good, but he still wants some of that redemption; he tells maggie his little screed about man-woman drama because he wants her to accept it. he knows the women and girls pay more to live in the same world, they don't get away with just existing while men get away with it all, but knowing that doesn't bring him any closer to looking at it head on. he's still asking maggie for something: accept it, get on the same page, spare me, and maggie says no, at least right then. eventually she does, then ultimately she doesn't.
anyway, I think it's interesting how different it feels to hear rust say what he says in that scene. you suddenly realize exactly how his words fall on the ears of reality. "at the end of the day you duck behind rationalizations just like the rest of them."