Reply To: What to do?
First, you didn’t make it clear that you’re not sleeping with this girl. A romantic trip for two when you’re not sleeping together is already a big, big mistake.
Second, and more importantly, you’re back to that bad power dynamic that existed before you made up your mind to win her back: you’re the nice, sensitive, infinitely flexible guy. She knows she’s got you. She can have you any time. You’re not so sure you completely have her.
You should have cancelled this trip, not because you were sure that she cheated but because you should never go on a trip that starts with this power dynamic.
Now, you have to pull way the fuck back and start again. The longer you wait, the smaller your chances of success.