@thefluffyshrimp (whom I cannot mention) replied to your post “It’s a common point of discourse in the fandom, and I’ve talked a...”
I think it's interesting how the game gives us almost no information about Rob/Jo's relationship. 99% of what we think about their relationship stems from people "filling in the gaps" with their own headcanons, like this. I disagree that the fandom paints Joseph as more honest than Robert. I see it as the largely the other way around, which is interesting, because it was actually Joseph who was honest about the affair...not Robert. All Rob told us was that he didn't like Jo and that Jo sucked, but he kept the affair hidden/concealed from the MC, which I thought was kind of odd. As a result, the only reason we know about the affair at all is because of Jo (he was the only one who was truthful about it happening). This does mean we only have Jo's version of the story, which could be wrong, but as of yet we don't really have any evidence to suggest he's lying. In fact, we don't really have evidence to suggest Rob is lying outside of the fact that he just kept the affair hidden from you. They could both be lying or telling the truth in different ways. Who knows. We don't have much to go on. But between the 2 of them, it did irk me that Jo was honest about the affair when Rob wasn't. Dunno why he did that.
We certainly run in very different circles in the fandom. My experience, especially my experience in the related RP community and with some of the more popular and high profile fandom members, has seen people always automatically assume Joseph is telling the truth, the whole truth, and nothing but—even to the point of saying that him disliking being lied to means that he would never lie himself.
While it’s true that Robert never tells us about the affair itself, and that we only know Joseph’s side, the existence of the photograph is already casting doubt on Joseph’s version of events. Robert and Joseph clearly used to be good friends—why didn’t Joseph mention that when he was telling the MC about the affair? If anything, what bothers me is the way the conversation with Joseph unfolds. Joseph front-loads the conversation with everything that could possibly discredit Robert—and he keeps the conversation focused on Robert and why Robert is disreputable. There’s very little of Joseph taking responsibility for his own decision. Whatever Robert’s feelings are after the fact, Robert had no control over Joseph’s decision, and Joseph keeps conversation off himself as much as possible.
As far as Robert, you’re right, yeah, he doesn’t tell the MC about the affair when they talk. But Robert’s intentions don’t appear to be to tell the MC about the affair. He appears to be there to ask the MC to step back and reconsider. Robert and Mary are close friends—remained friends even though apparently she knows that Joseph cheated on her with Joseph—and just as Mary cares deeply about Robert’s emotional health, as evidenced in Robert’s third date, Robert likely cares deeply about Mary’s. He isn’t there as a jilted lover (as many characterize him), or as someone who dislikes Joseph, or necessarily even as someone who Joseph had an affair with. He’s probably there, and he’s angry, as a friend of Mary—and a friend of the MC. He is only there if you make the effort to go on his first two dates; he is there because you built up a friendship with him. He’s there to put a stop to an affair in progress, for the sake of both Mary and the MC. He isn’t there for his own sake. If he was there to be self-serving, he would show up always, but he doesn’t. What Robert did with Joseph is, apparently, not important to him here, and it shouldn’t be because it has little to do with what the MC is doing. He, angrily, yes, is there to make sure the MC doesn’t make a horrible, horrible mistake. And it’s a horrible mistake no matter what Robert did in the past.
