I think she "had" to do it due to that subplot that it might jeopardize the plans that she promised her dead lover, but I agree, she made things so freaking bad by butting into the situation; I also agree with the other commenter that women on yaoi do tend to get hated (sometimes for no good reason) or made into this hateable character for plot's sake-- author-nim should've known better and thread more carefully in inserting her to the plot coz that's all she is so far at this point.
We are not hating her, we blamed her for whatever that make Hansol finally give in to take the decision he made rn. I know she is doing it for the plan she had with prof. Baek, but still, his relationship is not her business. It can jeopardize their plan, but she need to at least step back because relationship is kinda personal and private matter even for a partner business like her.
Since everyone's blaming I blame the blonde bitch everything was fine until she came