Wistash missed yet ANOTHER opportunity. He was there, he saw her being harassed, and he did nothing. Did he think that because they have their engagement broken, he shouldn't intervene? By doing that
I'm glad that this story won't be a case where she will return to her ex. These stories are not the kind where that's possible unless it's time travel isekai, and even then, it's unlikely to happen. She's going to be married to the emperor, and the ex will have to realize that he fucked up, and it doesn't matter if he learned his lesson. He will never get her back.