My mom has a severe gambling addiction. How do I handle this?

My mother has been gambling for about 2 years now. Compulsively. She has lost a lot of money and my step father is on the verge of a nervous breakdown. The last binge was a few days ago. Before that it was 3 months ago and he filed for divorce. She manipulated him so that he stayed. Now, he is thinking that he will try to press forgery charges against her. I have been tramatized by this. She has missed out on my birthdays, told me she doesn't have an addiction, screams at me..I have tried not talking to her for months on end, sympathizing, screaming, cutting her out of my life. I have just ended up hurt and depressed. I honestly don't know how to handle it. She drinks, does prescription drugs..Cutting her out of my life seems to help but it really hurts me. I feel abandoned and she places blame on me for her actions. I've been in counseling for this for a year now. Do I cut her out? She will probably end up going to jail and that is really sad for me. I'm so confused, hurt and angry.