I feel you so much about RPGs and everything in general, I look back and also usually feel bad for choices I've made. When it comes to actual video games I tend to be kind because the games are set up in such a way that the niceness tends to earn you more or at least not hinder you the way being bad does, but I've done bad runs of games for achievements and felt horrible about it the whole way too sometimes ):

Tabletops like The Resistance (or for me, D&D) are where I can get really nasty because I can be more finessed with that nastiness and get away with more as long as the dice are on my side XD

The Resistance seems to be a play on the Werewolf Game, which I've played at conventions and runs very similar but with a more fantasy theme because there's werewolves and the like. And in turn I know the Werewolf Game is the sort of inspiration behind a PC game called Town of Salem that I greatly enjoy as I don't get out of the house much anymore due to various things. They're all really good though, and it's all about either lying through your teeth if you're bad or hoping the people you're playing with are smart if you're good.

Perfect games though, those kinds. I can see why it's the most memorable moments for you, and most emotional ^^