Why? I don't know... the writing is confusing... at times... I think Lacey does it on purpose so she can get her Cuck kink fulfilled and it makes me think this is all a ploy to "condition" the MC to that eventual result, but... on the other side I also see dialogue that displays remorse for everything, her past, her actions, her pushing of the MC and the whole situation in itself.
All I can say is... I am confused.
When you are confused - unsure how to interpret the story - there are two options:
1. The writing is bad
2. You need another theory to interpret the well written story
All of us interpret stories. The easiest way to refer to the trope. The "typical" NTR story is sociopath bull (like Barty) and seemingly innocent but truly terrible wife. If you want a prototypical version so extreme that it's a parody of the genre try Lending my NTR girlfriend. And because that is the "NTR" story you want see you read this one it through that set of glasses. Of course the NTR story is itself just a encapsulation of stories that run through mass culture.
BUT this author tells us he deviating from the trope - so what now?
Just as an experiment try the "frog" theory when interpreting the game. Lacey will agree anything said by a sufficiently angry MC. ANYTHING. If the MC demanded that she acknowledge that she is a frog she would agree. So you need to take her "I'm selfish" etc statements with a big grain of salt. (1)
Also understand that she is not fully aware of her motivations. I mean who isn't just a little selfish? Get rid of
all selfishness and you don't take of yourself.
Her motives are mixed. She does want to make the MC jealous because that feeds into her "jealousy kink" but she also sincerely wants to get the MC to a place where he can accept all parts of her and that would be good for both of them. Unfortunately, the madness of both gets in the way. They aren't really a shark and a remora - they are two lampreys feeding off one another; neither of them understand this nor their motivations. Lacey doesn't understand that she is not always the one at fault, the MC is just starting to understand that he simply likes having something to hold over Lacey's head.
I honestly believe that a formal BDSM relationship could be a good ending for them. The MC would learn control - if you are going to do "breath play" you don't do it in way that could kill someone. Lacey could learn to satisfy her masochistic desires inside the bedroom and not to spread them to the rest of her life.
(Lacey, if you are reading this - keep those feelings for red bra night)
Then try different theories - "how would I interpret this if the narrator has PTSD" or depression. or multiple personality disorder. or if the character is a sadist? or a masochist? or a narcissist? Then test yourself - where does your theory fall apart? Be sure to apply each theory to both the MC and FMC.
And then get meta - how is this being written? What sort of literary tools is the author using?
You will eventually need multiple theories to get the game.
You know my answer to the queston about why Lacey seems to not approve of a "sharing" lifestyle even while pursuing one. Her college "sharing" days were an excercise in self abuse. She hates herself for being the person who has to stab herself with pencils to feel good. She hates herself for being the person who needs red bra night to feel sane. She hates herself because her dad told her she was worthless. S
he hates herself because the man she loves most needs her to hate herself. She hates herself because of internalized prudish norms: "good" people don't have sex with multiple partners.
For both MCs it is impossible to separate approval / disaproval or pleasure / pain - the milk is already in the coffee and can't be taken out.
(1) But wait! You say: You are just ignoring huge parts of the text if you say that. And to that I say: so is everyone who ignores the MC when he says he is wrong to feel betrayed by Lacey's college days because they were never together. You are ignoring the MC when he says that he is the problem. You are ignoring the MC when he says that he is the selfish one. You are ignoring the MC when he acknowledges that he can't forgive because he likes holding things above Lacey's head. Or that he is a bad person. Why is that - why dismiss the statements made by one character but accept the statements made by another?
Lacey: "because I'm a bad person"
MC: "Do you know why I'm such a bad person?"
Now I have my answers but I would be interested in hearing what you come up with after trying different theories on for size.
Again, my point is interpretation is inevitable but knowing *what* theory you are using makes you a better reader
