mpgpeg, first of all.. thanks for taking the time reading such half-assed explained comment XD.
Is the bartender the real reason Sumin and Seju can't be together?
No, as you stated before, it was their underlying issues.
not only that, but we agree that Seju is a daughter of a chaebol, their reputation is a huge deal. Take a look at this:
http://imgur.com/a/VvDmS
from there, you know that Seju's reasoning to Sumin's scarring was that her family were threatening them for having a homosexual relationship. It is shown that this kind of rumor was known at some level. You know why Seju accepted to see these blind dates ? TO PROTECT SUMIN !
why can't they be together, along side their issues (insecurities, trust.. etc) .. it's the BAEKS !. read the ending of ch27..
http://imgur.com/a/Dd3WL
they can't be together unless they leave the country. AND they won't leave the country unless they are together.
Now that her brothers sent her an assassin, who followed her from ch62 was not because what she said in ch71.. but maybe it's a more of reputation in a family that down looks at her. (this is a MAYBE.. I don't know)
Taking a wild, probably incorrect guess here... men?
CORRECT.. dammit, I like sharp people ! hehehe.. the conversation is interesting this way.
The main reason I'm holding back on accepting the hypothermia theory is... that it is kind of abstract for your average reader to understand.
hehe.. when was WDTFS ever directed to the average readers! the moment I saw ch50.. I was like, what do we have hereeee hehehe :P
anyways, they are good and well knowledgeable of these issues, for example the PTSD symptoms were slowly given to us from ch77 (the moment Sumin knocked the door and Seju was easily startled), through her eating disorder, mood swings in ch78, nightmares 79 ...etc until now. carefully putting things together. OMG, and Sumin's PTSD, and her coping mechanism (women and alcohol) does tell you that they know their stuff really well.. let alone the body language thing!
The bartender himself? I am not sure. It is noteworthy how Seju was affected by alcohol in chapter 84 though. It showed her low tolerance.
now this is tricky.. and depends on TG's mood for "breast feeding" XD.. because they already gave you multiple occasions where Sumin's assumption was just WRONG, and in this chapter Sumin was in a position where she was greatly misunderstood by Sungji but couldn't explain. Also, I don't know if TG would care to explain the obvious, since they already showed us in ch79, ch10 and all her blind dates that Seju dislikes men, period !.. they also explained Seju's weakness, not having any sorts medications at home and inability to protest on a kid like Sungji who excused herself inside Seju's apartment (and notice, Seju's driver DOESN'T drive her home ever (Think of why Sumin's assumption about Seju having guards in ch26 was wrong).. then again ch84.
it's really all about TG willingness to spoon feed AND how much shocking and twisting are they planing to show.