(financial) Questions about separation

Hi folks… Here is my short story. I’ve been married for just over two years, during which my wife and I have realized that we are totally incompatable. She has a son from another relationship who lives with us full time. Due to her insatiable desire for material goods, we live at about 100.2% of our means. From reading on this site, I understand that a one year separation is required for an absolute divorce.

Question - What are the legalities regarding financial matters during this separation. Who pays for housing, automobile, etc? With the current mortgage and so on, there is no extra monthly money which I could live on for the year to obtain divorce without putting them out of house, transportation, etc.

Any experiences or advice would be appreciated…