A few on here were interesting, but I figured I'd put my own personal trainwreck on display. Sorry about the length.
I have never been ditched before (except once when a girl claimed she did, except I said the magic words "it's over" before three hours of her arguing it, so I give her a moral victory at least), but to most of the girls' various credits, I didn't typically give them enough time. Then again, maybe I did, because after 17 I started the passive-aggressive "be a jerk to make them ditch me to save me some effort" when I wanted to get out. I'm 26 now, and the process is probably too refined to be healthy.
My first few actual "relationship" breakups were pretty mundane. I had the courtesy to meet 'em, told them it was over, whatever whatever. Well, whenever I needed to speed up the timeline to fit a new girl into the works without technically cheating on anyone, I would just give a call (or text, once I joined the modern world) and be done that way. Some of them were more catastrophic and illustrate why I should not be around any self-respecting female, though there are always more willing to subject themselves to it for some reason:
One, I woke up after a nap just after a (what I then considered) long shift at work to a pretty terrible smell floating around my apartment. My girlfriend, who had come in to make me dinner as a surprise, was cooking corn on the stove and put some parmesan cheese on it. She tried to make me sample some when I wandered into the kitchen. I refused, and after her repeated attempts, I took the bowl with a smile... then marched it outside, chucked it into the snow, and told her to get out.
A similar event happened when I was watching a movie and making turtle brownies for another girl at her place. She went into the fridge for something, and apparently noticed I'd forgotten the caramel you're supposed to put onto the mixed-but-not-baked brownies before I put them in the stove, and they were almost done. "Oops!" I said, and held out my hand for the little packet. Well, she made a game of it and said she was going to eat it right then, and made to open the packet, and for some reason this made me blow a gasket. I jumped up, ripped it out of her hands, put the stuff on the brownies, and left, never to return.
A third had this annoying habit of doing some kind of weird jazz hands thing over her face while laughing, which sounded like an irritable pigeon to begin with. I began forcing myself not to joke around her, 'cuz that would make her laugh. I think that ended with a text message.
A girl wanted me to give her the mardi gras beads I had found on her floor, so she flashed me. I'd seen her naked dozens of times before, but the light this time was just right, or wrong, as the case may be; all I could see were the veins throughout her breasts. So I gave her the beads and bailed out.
Another like that. I'd dated this chick for a couple weeks, and was pretty happy thus far. For some reason we never found time alone, and one fateful night, she and I were off work together and a power outage had shut down most of the town, so she suggested we go back to my place. Her shirt came off, I saw her push-up bra had grossly misrepresented the situation at hand, and that was that.
I'm sure there are more, but that's okay. You get the point. These stories are equal parts pride and shame, as they don't allow much closure for the girl. Some are strong about it, others go nuts and stop eating for weeks or whatever. Maybe a slightly less sudden end would be better. As for pride, at least I know I'm uncompromising and won't let these chicks spend their lives with me once I know I don't appreciate them anymore.