First holiday abroad with current partner was staying at her cousin's holiday rental annexe in Greece. I'd only ever holidayed solo or with partner, never with friends or family and not would I want to. Said we'd only have to pay for flight and hire car and would take cousin and wife out for a meal one night as a thank you but would spend rest of the time on our own.
First day there we spent entirely with cousin and wife, going to the beach they wanted and eat where they wanted. Second day same.
I told partner that for our first holiday abroad together I expected a lot of time just for us as she'd said we would get. We did get more time together but every day there'd be a couple of hours with her family.
We took them for a meal on the fifth evening and in our annexe that night I said that I would like to go to X tomorrow. "But it's our last day, I want to spend time with my family".
Balloon went up. Our first - and actually last - ever row. I said "This hasn't been a holiday for us at all, this has been you seeing your family. If you'd been honest from the word go I'd have said I'm not coming, you go visit family, and we'll have a holiday just us later in the year".
After sleeping on it she accepted it hadn't been fair that our first foreign holiday (and only my second ever time outside the UK) had basically been a family visit and apologised.
We have only ever holidayed just us since and it's been bliss. Doing what we want, not fitting in with other people. Do enough of that at work. Would never ever holiday with family or friends. Holidays should be about getting away, not taking some of it with you!