Drinking more at the house party before taking a break does have an affect. You see a montage of the other party goers before hiding in the closet.
After the confidence montage she seems a bit more confident but only in certain situations.
The club is to show that she becomes open to the idea of the free pass because she believes her husband is cheating.
The bride content does seem a Lil disconnected in some ways (some of the dialog doesn't seem consistent with how Yoon usually speaks)but overall it was fun.