Were you considering terminating therapy, or was it more an impulsive, momentary reaction to something but you still want to work with her? If the latter, I would definitely think it's better to contact her and figure it out. If you do want to terminate but feel ambivalent about it, maybe just send her an email or text saying so and also tell her you don't want to go back just to discuss this. I think it is perfectly okay to say goodbye to a T via email/text and also just ghosting. They must experience it all the time.

I don't know if most Ts would not contact a long-term client if they disappeared though... I more tend to think most wold reach out some to say they are still open, just not push it. If they push it, that's more of an issue (I had one of those). Can it be that the T also sensed that you could stop therapy at this point, or at least with her?