I broke up with a guy because even though he knew I was asexual before we started dating, he kept pushing for sex and when I kept saying no, started groping and stuff without asking because he said he was "entitled" to it since we were dating. I broke up with him, he said "No, I don't accept that" and informed me for the next week that we were "still dating" until he gave up. At that point, he grabbed one of my friends for a new boyfriend to spite me. Uh, dude, I broke up with you, why would I care? xD I cared more about the fact that my friend was going to be subjected to his crap than the fact that he was dating somebody new. He also bullied me until he graduated. What a winner, huh?
Then I had a boyfriend who, with a mutual friend, planned a breakup with me so they could date. On my birthday. They then both refused to talk to me anymore, until a little while later and the ex came crawling back, saying our friend treated him terribly and he wanted me back. Turned out he was still dating him and was lying to both of us (telling me he was single, telling him that he wasn't talking to me anymore). I don't know what he told our friend, because the friend came to me spewing venom a little while later about what I "did to him", but wouldn't tell me what I supposedly did, so who even knows?
I think those two are tied for the worst.
Unless you count the one who turned on me and said being gay was disgusting/sinful, etc and broke up with me, after dating me for months. Um, what?? Yeah, that one deserves a spot for one of the worst.
Or the one who got his friend to talk to me instead of him any time anything serious regarding our relationship came up. Seriously, the dude wouldn't even speak on his own behalf about keeping our relationship healthy. He even did that when I flat out told him I didn't think our relationship was working and that I thought we would both be happier with other people who were more compatible. He fled for the hills and sent his friend my way. Dude... seriously?
I sure know how to pick them, don't I? xD; I think the least dramatic breakup I've had was because the distance was too hard on the both of us.
I've been with my current boyfriend for four years now and finally is all I can say.