Thank you for your reply, Squiggy. I'm gradually finding some strength-- I'm trying to focus on job-hunting, and tonight is the first of three nights I intend to just go out and socialize on my own (something I have not done for literally more than 15 years).
It's still not clear to me what clout I have in setting boundaries other than the D-bomb itself. I can't withdraw financial support, because the primary income is hers (I do have an income from online selling, but it's not a living income). Am I just being too fearful at the prospect of withdrawing my friendly attitude? How are you setting your boundaries?