It's okay to be pissed. It's a part of processing it. But if you're still pissed about something that happened a long time ago, and the person in question has either changed or never intended to do it, then it's probably a good idea to drop it.
Guys I didn't even start the conversation nekonite called himself a useless piece of shit before I blamed him I left it unanimous so he wouldn't get flak for it.