Legal Seperation ?'s

Calif: My parents have decided to seperate. My question is this: My father is a retired veteran and my mother currently has access to all of the benefits from that retirement. If she does a legal seperation will she lose access to all of those benefits?
My other question is this: If they pay off the credit cards and close those accounts and open new ones in their individual names if anything happens to one or the other would they be responsible for that account as well. Basically if my father racks up debt and dies will my mother be responsible for it?
Would she be able to stipulate anything in the seperation agreement for either of the above ?'s