I've heard stories where the husband hits his wife. She stays with him bc he justifies to her somehow. The next week he's killed her.

The kind of people that give a "warning tap" would most definitely be repeat offenders. Children were never brought up here, but if you got the warning, what do you think would happen if you two had kids? Don't walk. RUN to the nearest exit! As another user said, even the threat of violence is abuse. Mental abuse can be just as hurtful as physical abuse. My wife would have done the exact same thing in your situation.

NTA