Rose and Kate were good friends for a long time so that would have been a special form of betrayal.

William grew up in a family for whom affairs were no big deal/accepted: Elizabeth seemed to take it for granted Philip had affairs and his longtime girlfriend was invited to family cookouts. Both of William’s parents had affairs. Diana’s parents both had affairs (and mom ran off with hers) The culture of class/wealth around him normalized affairs.

Though I doubt the middle-class Middleton’s values were ok with it. Maybe William did have an affair or a flirtation, we don’t know. If he did, they resolved it in their own marriage and it’s old news.

Harry loses by going down that road either way — no one will like such a private matter being brought up.

Even if