While I'm sorry that you had to experience that last session with her, it sounds like it at least REALLY affirmed you made the right decision!
It's true that different T's have different senses of where the boundaries should be. But it's not true that relational T's, or any T's, should have
zero boundaries, and she's lying to you and to herself if she thinks that's appropriate in a therapeutic setting. It's unprofessional and unethical.
She
definitely should have been willing to work with you on boundaries, and where you thought they should be. Her reaction was more like a petulant child than like a competent therapist. No wonder your angry part came out, mine would have, too!

You need a better therapist. It sounds like it's only "morally unethical" on her part because she's realized you're going to call her on her unprofessional behavior.

How...shameful of you.

I am sorry that you're having to deal with the aftermath of her, though. It sounds really difficult. <3