Backstabbing captain
I understand how you feel; if I would have had the good fortune to be hired I would have busted my ass as hard as possible to please everyone! It would have hurt me greatly, too, to receive that knife in my back. It's too bad, though, that this captain didn't notice you in the crew room before she opened her yap. For all you know, her colleagues might have spotted you and told her afterward.
I find this to be ironic. Here we are, coached by Kit, Irv Jasinski, and Cheryl Cage, too, I'm sure, to come across at the interview as friendly, easygoing, affable people. It makes you wonder if it is all an act; if so, some of these assholes are worthy of Academy Awards.
Having mounted my soapbox briefly, my $0.02 advice is you have to be practical and pragmatic. In other words, although it may tough, you must let it go. I skimmed through the posts and gathered somehow that you are on probation. If so, my advice goes double (for $0.04). The worse thing you can do is bring it up to a higher-up or even someone in the union. So, for at least the short term, you need to stifle yourself. Kill her with kindness. Be nice to the gal. You could risk a write-up if you don't, which would be the last thing you need. My mother always told me that when her boss gave her sh!t that she always responded by thanking him for telling her whatever.
Just a point of clarification: Do all captains expect the FO to be their bag caddy? If so, then you have to put up with it.
Hope that helps. Have a good last trip.