I dun really see it that way. audacious oh yes love that for her.. but responsible? absolutely not. from the start til now she's been doing exactly what she came to the show to do. why should she be held responsible for a stranger she doesn't care for? the only one responsible for holding up a relationship is the people in it. if it wasn't yuri on couple breakers, it woulda been some colleague or other after marriage bc that's always been the typa guy mungju is.

No way she says that there are couples on the verge of breaking up, while she’s literally responsible for one of them! My jaw dropped—I was like, ‘The audacity.’
As for what her boyfriend wants to discuss with her in private, it’s hard to know for sure. It could be about their relationship or how he feels about her involvement in the other couple’s situation. Private conversations like that often involve important or personal matters.