Unlike the "Social Butterfly" where one would "float" in and out of groups with relative ease and comfort, a social rhino is more likely to impose themselves upon a social clique. Not being able to take no for an answer, they will continue to try and "ram" their way into the group until they succeed when other members have given up trying to fight it.
Although ultimately feeling accepted into the group, one will often not notice negative feelings towards oneself behind their back.
Maria is being such a "social rhino", she just can't take a hint. I just wish I could tell her to piss off and find some other people to be friends with.