So my FIs old roommate and our mutual friend has a 'good friend'. I know her well, she was in my sorority. If they were dating I know I would have to invite her. BUT...they only see each other once in a while and consider each other friends with benefits. He brings her to every wedding as a date and she's a mess. She wears dresses that are way too small and all parts of her fall out after a few drinks. Do I have to invite her? We're ordering invites this month and they will be calligraphied at the same time, that's why I am asking this early.