The moment a person starts shaming their partner, making them feel undesired as a person, putting them down during attempts at healthy conversation, using silence to “punish” and control —as a rule it’s someone with NPD. And narcissists absolutely know what they’re doing. Moreover, they have that same dynamic of perfect relationship (first year or so) , then psychological abuse driving the partner nuts, then tearful attempts at comeback when the partner leaves.
So yeah, they’re doing it exactly because mind games (usually with several women at the same time) are their high.
I’m so happy you found the strength to get away for good, as so many women get stuck with narcissistic abuse for years.