okay but why was that dojin friend talking about dating someone of your same gender as som...

maybe he meant that it was disappointing for taewhan

he never said it was disappointing?
first dojin literally said taehwan must have been disappointed in him for being in a relationship with taehee, and yeonwoo then added that taehwan probably didn't hate him for it as much as dojin might have thought
nowhere in the conversation does yeonwoo say or even hint at same sex relationships to be something disappointing
were we even reading the same chapter?

yup