Welcome!
You have found excellent peer support, anonymous and remote, but we have "been there done that" and have a wealth of past experiences that collectively are a treasure trove of what generally works and what generally doesn't work.
This is probably a time for you to be pragmatic...
It is what it is. Do what you have to do. Of course, first educate yourself on more aspects of how Borderline Personality Disorder (about half of these PDs are "acting out" inflicting pain and suffering upon those closest to them).
You are blamed for everything because of course that person is never at fault. Blamers, Blame Shifters, moods morph between good and bad and back again almost by the minute, accusers, predictably erratic and unpredictable, etc. You have to understand that the person's perceptions and world view are skewed, and the rants and rages are prone to become more and more frequent.
An important question: Do you have children? If not, don't start. If you do have children, the custody and parenting schedule issues can make a separation and divorce even more difficult — and important — than the financial aspects alone.
To help you deal with her, read Henry Cloud's
Boundaries. Before you begin a divorce (even during an initial separation) be sure to read William Eddy's
Splitting: Protecting Yourself While Divorcing Someone with Borderline or Narcissistic Personality Disorder.