What I like: strong female characters who can act with conviction, even if imperfect.
What I don't like: waffling melodrama, that isn't VERY well-framed, with artificial character motivation to drive plot.
Rereading the entire manwha, time and time again she mentions "I'm gonna divorce Aiden" or "I just have to avoid getting closer to him". Everything she does is pretty much setting up for the attempted divorce arc. We've known since the early chapters that Erin will have to divorce by age 20 if Aiden is to properly be set up with Yulia with no lingering feelings. And we've pretty much also know that Erin has done a horrible job of keeping a platonic relationship with Aiden.
The main thing holding her back is that she's not just Erin, but also that she was a 29 year old Korean Officer Worker. There's an extra 29 years of experience that's guiding her decisions. And that's pretty much the reason why she's stuck with the Divorce plan as long as she has. Erin would totally be fine with an obsessive love, but from the KOW point of view, that's pretty much how she ends up getting killed in the first place. And now she's in a much stronger position than original Erin to tear Aiden's relationship with Yulia apart. She could fully indulge in her desires for Aiden, but she's so focused on what she thinks will make him happy that she's ignoring her own feelings. Those 29 years of her past life are a blessing with how much she was able to change for the better, and a curse because she's stuck with the idea that Aiden could just be taken away from her the moment Yulia pops into his life. Ironic now that her knowledge of the novel is pretty much the one thing keeping her from embracing this life's happiness.