Her behavior towards the mc starts to change at the charity gala and is very different at the home dinner where they talk a lot about their past and memorys.You and I probably selected pretty closely with Allison - I've tried to be understanding and empathetic the entire time since MC is the one that cheated, but I felt like by the end of this episode it's pretty obvious on that path that the MC is doing literally everything he can to help Lily and Allison so any reasonable adult would lay off from the constant attacks given the circumstances but Allison mostly just continues to berate him throughout, so I have begun to pull away from Allison by the end of Episode 2, even choosing not to do the dinner date with her.
I do hope those of you on her route enjoy though, she's a cutie.
Another thing which i didnt saw mentioned so far:
They were obviously childhood sweethearts who married early and he was probably the only love of her life. The MC didnt only cheated on Allison. He disgraced her.
It wasnt just a hookup with a random girl while being drunk or something like that. Both the MC and Allision were supposedly a power couple at their company and higly renowned.
And he cheated on her with a cooworker who spilled the affair to whole office and used the affair to climb the corporate ladder. Everyone at their company knew about the MC's cheating on her afterwards. At this level its not only having sex with somebody else, this is a way deeper betrayal of trust.