"I once dated someone who said she was polyamorous, but she burned me real bad, so now I think polyamory is bad and I'll never try it again"
*bangs head on desk* What would you do if I said:
"I once dated someone who said he was monogamous, but he burned me real bad, so now I think monogamy is bad and I'll never try it again"
"I once dated someone who said he was christian, but he burned me real bad, so now I think christianity is bad and I'll never try it again"
I once dated someone who said he was Irish, but he burned me real bad, so now I think everything Irish is bad and I'll never have anything to do with the Irish again"
I once dated someone who drove a taxi for a living, but he burned me real bad, so now I think taxis are bad and I'll never ride in one again"
Did it ever occur to you people that maybe that person was just an asshole? Or, more plausibly, that you two were just not compatible and the relationship configuration had nothing (or very little) to do with it? If we were to base our opinions on activities and people and systems based on the very first time we tried something and it ended poorly, our entire society would not be fixated on monogamy, we'd never drive cars, we'd never play sports, we'd never hold jobs, we'd never do anything that didn't work out exactly perfect the first time we tried it. It's a good thing for all you straight men that women don't take this attitude about sex! If we gave up on things because we got hurt the first time we tried it, you'd never get laid again.
This is not a rant against people who prefer monogamy, this is a rant against the rationalization that polyamory is bad (or is not right for someone) simply because one time they met an asshole who claimed to be polyamorous. Monogamy doesn't have such a hot track record either and I don't see too many people giving that up after the first relationship disaster, or the second, or the third, or the fourth, or the forty-fourth. No, apparently, if it's poly, you can assume that one bad experience means the whole system is bad and everyone who does it are lying, cheating, insecure jerks like the person who made you feel bad, but if it's monogamy, you just keep plugging away at it, suffering setback after loss, after pain, after heartache until you die.
Because if he's monogamous and he hurts you, he's an asshole, but if he's polyamorous and he hurts you, it's because he's polyamorous.