Once, by an unstable guy in my school. We went on exactly 1 date, total train wreck. First he changed all of his classes to be in mine. Then I spotted him waiting for me in various locations. I tried being nice. Told him he couldn't keep doing that, when it got worse, with him actively following me after school to try to find out where I lived, I told him he had one more chance to back the fuck off before I called the cops. He attacked me, I broke his jaw.. With my Face! They never expect a headbutt