Those are 2 different issues, though. The spouse has to decide whether to stay or make a big deal out of it. I don't care about that decision; every relationship has its own dynamic. I don't have to understand the relationship to make a determination about whether to vote for someone.While it makes for good TV... You know, I actually honestly don't care, and here's why... people are freaky. I have no idea what type of relationships the Clintons or the Trumps have maybe Hilary and Melania knew about them, maybe they didn't care. If that's they thing, it's not my place to tell them how much I disapprove of it. If Melania wants to come out and say something expressing her displeasure, then I can take issue. But if she's going to be quiet, I see no reason why I should really care also.
If there's a candidate who has an openly open relationship with their spouse, then that's another data point to consider. Kinda like a, "At least they're honest about saying they don't treat the vow seriously."
Also, though, if the couple is in a non-married relationship, I would view that differently. If they haven't made the promise, then there's not promise that could be broken.