You do realise this is a business transaction don't you?? forgiving GFs or FWBs is totally different. The OP here was a regular paying customer of this escort, a regular source of income for her. It sounds to me like she has become complacent and believes she has someone, like yourself, who she can just mug off any time knowing they'll come running back.
She is a professional and should act like one. The booking was confirmed, the OP turned up, she didn't even have the decency to tell him the same day.
What she can or can't afford just doesn't come into it.
Maybe I'm delusional & or fluffy, but with the few WG's I've seen for repeat business, I've not seen it as 100% transactional. I felt there'd been a genuine click, and was more like 80% transactional / 20% relational.
Just like with most of my of civvy gfs, I've not seen it as 100% relational, I'm still a bit old fashioned and think the man should mostly pay. I'm comfortable with that, being as I've never been good looking, but have been ok at earning. Maybe this is soft of me, but I'm far from alone in thinking like this.
It seems you hold WGs to a high ethical standard, which is fair enough. Me, I agree some have a true professional ethic, just as strong as the best business folk or civvy professionals. But others are from a lower working class background, they don't get taught ethics, and wouldn't understand why messing about a punter like that is wrong.
If the OP just drops her, then fair enough, but I doubt she'd learn unless maybe he txts her and tells her why. But if he gives her a lecture on why it was wrong, & then a spanking, she might learn some ethics. It's a public service thing.