I've been accused of attacking people because of the things my characters have said or commented on IC in the past, and felt a lot of backlash for it which both shocked and floored me because I thought it was pretty understood that certain characters of mine were aggressive/mean/whatever. It sucks.
I totally understand what you're saying about not talking to people OOC and joining games without like, 'contact lists'. I think it's something I might look into in the future.