I agree; I would, too, have returned with her, either after a short while of continuing or immediately. But since she insisted, they may not be the most considerate people on Earth, but it doesn't make them awful people either. Also, I'd consider the fact they had just learned she was trans (if I understood well) an attenuating factor; they might have wanted time to digest the news.
I'm not trying to defend them; maybe I'm too soft, but well... I wouldn't hold a grudge if I were her. They didn't do anything wrong, after all; they just didn't do the best thing. I mean, it takes very empathetic / very nice people to see through someone's smiles and "no, no, I swear, go on without me, I'll listen to music in the car and you can text me anytime!" and provide unrequested support. Anyone below that isn't necessarily a bad person.