Not the best way to handle a situation

Back in my younger days, I had a bit of a temper. I still do, but it flares less often. In college I started learning fighting might not be the answer. (Partly because I lost several) About that time, I met an awesome woman. Over a few months I started developing more than a passing interest in awesome woman. To my disappointment, she only saw me as a friend. Over the rest of the year, I watched two guys in a row break her heart. We kept in touch over the summer, and as the next year began, she met guy #3. I didn't know him other than in passing, so I figured my initial distaste was mostly due to him being the object of her affection. After a few months he showed his true colors and hurt her on several levels. Around this time awesome woman and I had a misunderstanding resulting in me getting the silent treatment. One day I was in the weight room working on the stationary bikes when guy #3 walked in. I had visions of a horrible weightlifting accident about to happen, but decided I needed to let it go. He started making small talk, and I tried to be civil. He asked how awesome woman was, and I said I'm not sure, since she hadn't spoken to me for a couple of days. That's when he decided we had some sort of bond. He started sharing details of the things he did to hurt her, saying how glad he was he 'got in, got out'. Weightlifting accident flashbacks started creeping back into my head, but I ignored it. Getting dressed in the locker rooms, he said we should hang out sometime, talking about the wild and crazy times we could have. He said he'd do anything to win a bet, and gave some examples. I bet him $10 on the spot he couldn't fit into one of the lockers enough to close the door. He climbed in, closed the door and said "you owe me $10 sucker!" with a huge grin on his face. I calmly snapped a padlock on the door and slid $10 through one of the holes and told him "You earned it, oh, by the way, when you get out of there, if you ever mess with awesome woman again, you'll wish you were locked back in here."