Actually, I have to say I agree with him. Kinda.
He's right that she's selfish and inconsiderate, repeatedly pushing far past his comfort zone despite being unambiguously told to stop and why. I actually don't mind this; characters in literature of this type tend to be perfect, it's refreshing to finally play a game where they aren't.
What's been bugging me is the way Erik reacts (or rather, practically doesn't) after the cave incident. He's already feeling guilty about what he's done with her, then she basically pins him down and rapes him while he's too disoriented to resist, and then... almost nothing? He feels a bit guilty and there are gestures at being angry, but in his thoughts, there are none of the emotions you'd expect; no real fury or pain or sense of betrayal or much of anything, really. Supposedly he feels ashamed and guilty, but then a day later he's agreeing to get drunk with her despite surely knowing where that would lead, so apparently not that ashamed. It just feels too easy, like you didn't really capture the angst he would be feeling there.
I don't mean to be too critical. In general, your treatment of these characters and the taboo itself is quite sophisticated. It just made that scene and its (lack of) fallout disappointing, IMO.
Because he feels the same, he can't be truly angry at her. The guilt is just a facade, an excuse that will get overcomed over time.
The entire premise of day 6 is to show they can't be without each other. For that I made the deliberate choice to have them mostly converse through the phone, eavesdrop, have internal monologues... They don't interact much directly until the night.
About the wine, it helped because he wouldn't have had the balls yet to talk about those things with her without some alcohol during that night. And then the next day the full reality of the situation comes crashing down and he breaks again.
