ok, since the children are in daycare, it sounds like it's time to DOCUMENT every friggin thing. You document in point form, writing down dates and times, and a very un-emotional description of the event:
"Monday, February 1, 2011, 8:30 p.m. Wife gets into a rage after stubbing her toe. Verbally assaults me."
"Tuesday, February 2, 2011, 12:30 p.m. Wife is passed out on living room floor"
Do this and slowly build your case. Start stashing important paperwork elsewhere (like a safety deposit box at the bank, or in a locked cabinet at work), just in case you'll need it later on.
If you are considering separating, you will need documentation and legal representation, no matter how crummy the legal system is. Heck, navigating the system can't be worse than the rollercoaster ride you're on now...