re: How do you baws split expenses with the wife?

The general rule in LA is that marital funds are subject to equitable distribution. When a separation takes place, each gets party gets 50% of the shared property and each shares 50% of the shared debt. What you bring into the marriage is your separate property and stays with you when the marriage ends, unless there is some evidence or a presumption that you made a gift to the marriage. Hence, why lawyers like seeing this when alimony and asset dispersion is pre-negotiated.

A general rule of thumb is that the money you brought into the marriage and kept in your own account raises the presumption that it is your separate property. If your spouse produces a letter or email where you said you were holding the money for a marital purpose, the presumption is defeated; this is marital money. Money put in a joint account raises the presumption that it is marital. A court should (and usually does) require the spouse to present some evidence to support a claim that it is separate property.