How to Deal with a Ghosting Client?

In November, I accepted a contract for a multi-month project. It was going very well and the client was engaged, always prompt with email responses, and happy with my work. Things slowed down with the holidays coming, and I let her know I was available during that period if she wanted me to work on it. For 2 weeks, I sent a weekly update as I had been before, but heard nothing back. It’s now been total radio silence early December, and it’s time sensitive work.

Pretty sure I’m being ghosted, which is a professional insult and is causing me significant financial trouble (I know better now, but I trusted that the project would take several months as originally planned).

I could use some advice on how to proceed. Is it worth it to reach out one last time, or is it clear the ship has sailed? Should I revoke her access to the Google Sheets doc I built for the project? I don’t want to be petty but I also don’t want my work to be exploited.