Boy, you sure have my deepest sympathies in dealing with your mom. Personally, I feel that you've done everything that you could to help her, understand her, and communicate with her. She sounds as if she has a personality disorder - most personality disorders (narcissism, sociopathy, borderline personality disorder) are learned behaviors and not, by any stretch of the imagination, organic in nature. There is no medicinal treatment for personality disorder, though psychiatrists have tried numerous pharmecueticals to no avail.
At this point, it it were me, I would be maintaining a running log with dates, times, quotes, etc., and be very, very careful to leave out any emotional or moral monologues. I would be collecting every note and letter into a file. I would then consult an attorney that specializes in real estate. I would then get to an abuse counselor ASAP so that I could learn tools and techniques to curtail my emotional responses - this is the crux of her control. If someone can cause me pain, I've given them too much control over my emotions.
And, never, ever feel that your concerns are trivial, frivilous, or unimportant. You are (and, have been) suffering emotional abuse and you have every right to feel outrage, betrayal, and the rest of it. Now that you are fed up, find a way to healing for your Self.