I'm so sorry this happened, but you can see from the responses how frequent an occurrence it is.
It happened to me most memorably at university, a friend and I got invited to visit an island off the coast of Wales with one of her flatmates (even though we had NO interest in the activity, which was sold to us as an, oh my diving mates are so friendly, you'll love the socks of them, let alone the wetsuits, blah, blah, blah), it's a lovely island, you'll really enjoy exploring it etc etc. Well, to cut a long story short, the weather was awful even for Wales, and they were all hideous (behaviour wise, I mean) and anything but friendly. We later concluded she'd asked us to help make the petrol costs more affordable.
And I currently work for an organisation where the little team I work for s constantly made to feel second rate, excluded, ignored, talked over in meetings by the team that took us over more than two years ago. It's actually one of the main reasons I'm now looking for another job, as it's not going to improve any time this side of the next millennium unless they all get personality transplants. Ironically the team that inherited us is also the part of the organisation that bangs on every five minutes about exclusion, pronouns, etc and is responsible for it. Jog on, HR-lite; your actions speak far louder than your weasel words...
I have had lovely experiences as well, though, a few years ago a friend and I joined her walking group in Scotland for a week in a large house we all paid to rent. Although we didn't join them for all the walks as we were nowhere near as fit as they were, most of them (bar two little tithery girls) were very welcoming. They did all work in different organisations though, not all workmates from the same location.