Minimize your expenses. Remember, cash is king, so dont rush out and pay off your debts. If you have credit cards, try to make the minimum payments. Noodles are a great meal and can be purchased for less than a $ for an entire serving. Cut unnecessary expenses. Cable TV is not necessary, neither is internet. Find your local library and use their internet. Dont refinance cars or open up HELOCs if you already own the asset or have equity in it.
Doing so will allow them to remove such things if you have to file for bankruptcy. How long have they been married? It is important that if he is out of the picture to get your mothers name and you name off of any credit cards or accounts (VERY IMPORTANT). See if you can get a fraud alert on your credit report to prevent him from opening up credit cards in your names. Go to annualcreditreport.com and get a credit report for both your mother and you to see if any rogue accounts are listed. Use ChexSystems to see any banking accounts that both of you may not know about (and you may be listed on) consumerdebit.com. Use choicetrust to see property, criminal filings and legal filings for both of you (choicetrust.com). With ChoiceTrust, click on "Personal Property" then click the title near the "One free report per year". All are FREE under FACTA.
At this point, a divorce may be your best route. If they have been married for awhile, any debts he accumulates will be shared with your mother. This is very very important. I know a few people who where married, one left, and 1-2 years later, they find out they are responsible for a 60k credit card that the other spouse ran up.
If there is ANY physical abuse, seek help. There are groups that will protect both of you. If abuse exists, they will house you in a safe place, provide security and possibly temporary employment. If debtors are threatning you, call the police and file a report.
Take action and seek help. Join a local church and let them know of your situation (Really, go to the pastor and ask). They will not give you money, but they may help with food and help your mother seek employment (regardless of your religion)