As much as i want to know whether Emily really did what i (and i think we all) assume she did, so i can make my choices respective of that, i kind of like the fact that this game has a little bit of mystery aspect to it (if that's what you call it), same thing with the blonde chick. gives us something to think and speculate about.
The thing is, that the author/developer have approached the whole Emily thing from the worst possible angle. At the very beginning, we had a statement of her cheating on the MC, then sometimes later, we had a flashback scene that didn't really revealed anything important about the nature of said cheating. Ever since that, nothing happened on that front, meanwhile Emily gets thrown into our face rather often, and the only thing we can choose if we go along with it or just ignore her everytime.You basically put in a situation where you have a choice while missing important information regarding to it, which is the worst possible way to keep up the "suspense" or mystery.
There's at least two ways that this whole situation could've been done, and it wouldn't feel like that they are screwing the players on purpose.
The first is that every time the player meets Emily for some reason or she gets a part in the story, which seems to be an occuring theme, a piece of information could've been revealed about what exactly went down that night and why exactly. That way, the player slowly could get a better grip on the whole situation, could decide if it's worth pursuing her or not, and the mystery behind of those events could be still kept up, instead of just blocking anything about it but expecting the players to go route A or B.
The other, is that after a while, not too long though, the whole thing is revealed in one in a form that fits the storytelling. It could be either a flashback, like the previous one, but instead of giving vague information, it gives the whole picture. It could be a sit-down between Emily and the MC, to talk out everything and decide where to go from that point. It could be the main character telling the story to a third party, when his past relationship with Emily comes into question, there were opportunities to do so already. Or simply a narration from the main character where he reveals to the players itself what went down at that particular night. This doesn't keeps up the mystery, but at least clears the air up (probably), once and for all to the players, and they don't have to go back who knows what point to decide to keep or drop Emily permanently in the story, and neither the developer has to make every Emily scenario into one where the MC acts like an utter dismissive dick to her.
For both solution, there's a window of opportunity, that already ran out. The problem with the whole Emily situation is that both in and out of game time, you have zero information regarding to what happened with her and how to deal with it. Because that point has passed, it's not an exciting mystery anymore, but an annoying bush beating that will frustrates the players more and more, rather than making them excited. The more this dicking around of her situation keeps up, the worse it gets.