Are you okay with all this? You've been amazingly strong through this, but I could understand if you feel as though you may be moving backwards. As long as you are keeping up being friendly, etc, then her current reactions are her own problem. Sounds like a child basically saying, "I'll show you". She'll work through it one way or the other. You've set a few boundaries and she's overreacted to them (although the "inevitable divorce" part may have been a little over the top unless you really believe that). I personally don't know what to believe. Part of me thinks she'll work through the ramifications of all this (after all this time of not having to face reality) and will eventually move your way. I just don't get the feeling that she's done with you. Maybe it's just a gut feeling, but I do get that sense. I'd play it out and see where it goes. The part-time golddigger, "maybe come back someday if you're available", don't want divorced but don't want you, thing was really pretty much an untenable position for you anyway. Plus, you didn't do anything that most separated and divorcing couples don't do....you asked to separate your accounts and get your house key back. Whoopidy doo.
In the end, it's not the years in your life that count. It's the life in your years. Abraham Lincoln
It is hard to fail, but it is worse never to have tried to succeed. Theodore Roosevelt