IMO you committed a pretty serious boundary violation. That's how I would personally feel, and I think your T felt that way too. It would be unethical for her to continue to treat you if she no longer feels like she can help you.

You've asked a lot about whether your Ts actions were ethical or not. Do you feel your termination was ethical? What would a lawsuit accomplish? Do you want damages? Or are you trying to find a way to be heard or communicate with your past T?

I don't personally think you would be successful with a lawsuit.