While this is awful and appaling, it’s not at all uncommon. Your ex-boyfriend had a typical male power fantasy, where he gets to subjugate other males and win a woman as a prize. This kind of fantasy is spoon fed to them since they’re really young, by all kinds of media. Just look around and see how many movies and games, and even cartoons for young children, have plots based on a male defeating another male and taking a woman as a prize. It’s the classic “Damsel in Distress” trope.
Anita Sarkeesian, the scourge of doritos-covered sexist nerds everywhere, made three excellent videos covering specific iterations of this trope in video games. In these videos, she explains in detail how men are taught to see women not as peers, other human beings with a full range of emotions, but as interactive objects that will provide them with rewards (sex, affection, domestic labor) once they secure them from other males. Still quoting Sarkeesian, “In the game of Patriarchy, women are not the other team. They are the ball”.
This is exactly the kind of mindset your ex-boyfriend had. In his fantasy, he would win the “game” by defeating another male, probably by inflicting physical violence on him, and take you as a prize. This would make him feel more masculine, because masculinity is based on constant competition between all men, and in his mind it would also make you be grateful to him, because he didn’t consider you as a human being capable of trauma and mental distress, but as a damsel he must rescue, a princess in the tower that he, the mighty knight in shining armor, would yank away from her captors.
I’m just glad you’re not with this delusional piece of shit anymore.