Naoki, unfortunately most people act that way, although it doesn't always go one way. I've done the breaking up a few times, and there always seemed to be a friend or two who wanted to be a bastard afterward. Almost like a "how DARE you break up with MY friend?"
Some people don't seem to realise that nobody owes it to anyone to stay in a relationship if they don't want to be there anymore. Why HER friends are dogging you, I can't imagine. You weren't the one who broke up with her. Sounds like she's telling them some shit that's not true.
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