Ehhhh, the moment I took control of my direct deposit and denied XW access to my cash, was seen as a 'hostile takeover' of sorts and really pushed her over the edge. Couple that with the 'bravado confidence' of speaking with a L this early on, would tell me history is about to repeat itself, except it's your grief this time etrain.
I would address the finances quickly and calmly with her. Hell I even gave mine advance warning, to which she must have thought I didn't have the brass to do. I would then address the issue of joint accounts and what is who's there. Just do it with a nice calm casual, "well this is what you want so I wont stand in your way attitude". I know easier said than done, but, you still have a chance, I don't, I made these mistakes, so take them for what you will.
Me 35/XW 33 S13 & S12 M: 10/17/98 OM & S: 07/08 D final 06/09/09 12/03/09 - 06/13/10 "Piercing" 06/13/10: Engaged to Re-marry 10/17/10 06/25/10: Expecting baby #3 2/14/11