I would be upset too. If my current T would forget an appointment, I would be very angry and hurt, but I wouldn't quit seeing her. But if a new T would forget an appointment, I would quit and look for another T. I think I couldn't trust her/him.
I was once forgetten. It was my first day of grouptherapy and the T was supposed to get me, but she forgot. I felt so ashamed. And I've never been able to trust her.
So if you would feel like that, then you've probably made the right decision.

I hope your new T will be good for you. I understand about losing faith in therapy. I've lost that too. I now have a good T and pdoc, after years of T's who didn't care or didn't really know what they were doing.