From her perspective, I honestly don't know what I would have done in her shoes - sneaked out feeling like a criminal for going somewhere I was so obviously not wanted, or if Larry's aunt came back behaving as normal obviously thinking I hadn't heard, pretended I hadn't so as not to embarrass her.
Good question. I think I would have left, if possible, then had a long hard talk with Larry afterwards about why family preferences do not trump my feelings as a partner.
Agreed. Poor woman, whatever she did was probably going to be wrong. If she knew that she was specifically excluded, then she shouldn't have gone, I think most of us are agreed on that, but in that case if Larry went she would probably have been left feeling that he didn't value her, and if he didn't go, she would feel guilty (well, in her shoes, I would - obviously we know nothing about her so I'm guessing). If she knew she wasn't invited but went anyway, she's in the wrong. If she didn't know... how horrible! Then if she stays, she knows she's the reason for (although not responsible for) a family row that they've all heard and half of them are pretending they haven't while the rest snub her for something that isn't her fault. If she goes, the family row will probably be worse because there will be no pretending that it isn't happening and either Larry goes with her (bad for the family) or he stays (bad for her).
I think we simply don't know enough about the length/depth of her relation.ship with Larry, and as other posters have pointed out, the precise relation.ships/lack of relation.ships that other members of the family have, to judge whether the aunt was being fair not to invite her, but I think that Larry has managed to put her in a horrible position. If he felt so strongly about his relation.ship with her he should have said 'we come as a couple or I don't come at all' and then fought out that
battle. Personally, I would have based it on whether Girlfriend had already been introduced to the rest of the family. If yes, then she's serious and should have been invited. If not, there's a case to be made for 'not this year, please, Larry'.
I do get that Aunt didn't want sundry hangers on - my family has a tendency to collect lame ducks, and Christmases when I was young included the alcoholic divorced wife of a friend, the foreign visitor whose passport had been stolen and who couldn't go home, the elderly neighbour, the vague acquaintance with nowhere else to go etc etc cont page 94. There were other times when we did
just put our respective feet down and say 'family only'. But the catch of that was that we didn't say either 'everybody... except John' or 'family only... except John'.
I can understand OP's friend being chilly to Larry - ignoring him is probably a bit childish, but choosing to be engaged somewhere else is OK - but I do hope that having allowed her to stay, the family was civil to Girlfriend.