This book will focus on the rights each spouse has under certain laws, situations, and circumstances, and how the division of the property will be decided by the court or through negotiation.
In our state, if there's a question about disclosure... even if there's not... most decrees have a clause about "undisclosed assets", meaning if you find out in 2 years that your ex won the lottery with a ticket bought with community funds the day before he kicked you out, and he didn't claim his winnings till the day before the two year lottery deadline arrived, in an attempt to keep you from getting a dime of it... well, you can go back and lay claim to a fair share.
On the other hand, this does not take care of disclosures about inheritances & such, which you may not have any right to have part of, but which may be part of your reason for being willing to accept less than what's fair (I'll only take 30% of the total property because I got that little inheritance from Dad and I can afford to live on next to nothing, but you take the other 70% because it's all you've got ... I've heard people getting FURIOUS when they negotiated under these types of assumptions, only to find out that the ex was a trust fund baby and the only reason they bothered to fight over the community assets was to mess with them.)
Full disclosure is always good.
And an official separation may start as of the day they're not living together, but that doesn't mean the creditors recognize it... it doesn't mean there's any separation agreement that is enforceable for him to pay her utilities... it's basically meaningless until she files something at court.