Well, "at the same party" might not be that ridiculous. Depends on the party and its goal.
Merely knowing/being friends with the guy though should not be reason for disgrace without further evidence of anything bad on one's part.
>It is yet another example of how public discourse has degenerated to the point where we are attacking people first and refusing to ask even some basic questions before branding someone as guilty by association.
I think the reason for the public displays of disgrace is to tell us how "good souls" they are, more so than any real concern for the victims. Most people could not care less and will forget the whole thing in a heartbeat, but they still like to participate to the collective hate ceremony - and even better when the person to hate was really an abuser!