I disagree that either one has more right to be angry. The single girl was obviously hitting on Jung and then he went out with her a second time afterwards (because he was oblivious true, but Sukhee has the same excuse!). Married Kang met up with Sukhee by accident and it sounded to me like all he really wanted was dirt on Kang (his face when Sukhee said she still wasn't disappointed). On top of that, Kang CALLED JUNG to come retrieve her, which if you think logically wouldn't happen if he were cheating with Sukhee. No way would that redhead have done the same as Kang. And neither Sukhee nor Jung had ANY way of knowing how innocent their partners were in the outings until they talked, like they did in this issue. It's really not fair to give one character a pass for being oblivious to how their actions are viewed and not give the other character the same pass. My only complaint about the current situation is that Jung apologized more than Sukhee. I find it interesting that Sukhee put a lot more effort into communicating with Jung while they were apart (phone calls, texts) but he put more effort into communicating face-to-face.
Sukhee is dealing with all the preparations for a 1000-person party with a long list of formal rules and details while her fiance is giving her wrong advice (innocently but thoughtlessly) about what matters to his family. Kang sits down at her table without an invitation. Jung fails to repulse a woman literally hanging on his arm, more than once. I fail to see how Sookhee a "bad girlfriend" if Jung isn't a "bad boyfriend" at the same time.