I was thinking the only reason for Aubry to be crying and saying the vote is hard was because likely Jason won Immunity forcing them to turn against one of themselves...and Cydney asking Aubry "if it came down to it would you vote with me or THEM"

I can think of another possibility. I think the disagreement could be over whether Tai or Jason would be targeted. If Cydney wins IC, I could see her pushing to get Jason out of the game so he can't win any more challenges. Meanwhile, Jason and Michelle want to target Tai because they can flush out the idol and Jason has his revenge.

Aubry is torn on which way to go because she's torn over what would be best for her endgame. She could vote with Tai to get Michelle out of the game - Aubry knows Tai could save himself with the idol, but will the jury hold it against her that she sold out her alliance to keep Tai. Keeping Jason could be an issue, since Aubry knows he considers her a challenge threat. And if Tai's out, she's lost her key alliance member. She sees problems with each possibility and is trying to figure out which is the right one.