In ghkkpm the issue is that every impactful scene of V reprimanding pp has been subsequently diluted/ruined by Vs ridiculous character arc and progression. It took him a long time to see pp's true colors , her pettiness, her cruelty , her obsession, her immaturity. Yet he keeps acting as if he has amnesia , never is wary of such a dubious person and allows himself to be manipulated by people who have been established to be untrustworthy, irrational. He is constantly seen as failing Sai, her trust in him and their bond, the sanctity of their marriage due to the influence of extraneous factors. Such a person is stupid, untrustworthy himself and therefore Sai needs to leave for self preservation. Heartache from separation is better than the incessant lifelong angst and torture.