Should I report her to her Parole Officer?

I have a big problem. My husband is a recovering alcoholic. He has been sober from alcohol for almost 6 months. He is also addicted to pills, mainly xanax and lortabs. He does good for a while, then relapses. I understand this is one of the hardest addictions to try and stop on your own and I am trying to give him all the support I can to help him through this. The problem is… his mother keeps giving him pills behind my back. He finally confessed it to me and now I am stuck with a hard decision to make. What to do about his mother. Do I cut her out of our lives? She is on parole for drug charges herself as she is an addict.. Family traditions huh? I am so angry, I am considering calling her Parole Officer explaining my situation and informing him that she is still doing drugs and every time they call her in for her drug test, she has been using a detox to pee clean, and the shampoo for the hair follicle test. I know this because she told me this. She has already peed dirty once and she denied it and the PO let it slide. Should I go to her PO and tell him what I know to get her out of our lives and away from my husband? Shouldn’t I do something to keep her away? I need help… Please
Mature advice only please. I am serious. I need honest mature opinions to this problem. I am trying to save my marriage here.
I have talked to her repeatedly about giving pills to her son and the last time I talked to her, she said, “Well you know he’s never going to quit taking pills”, so I told her, “Not if you keep supplying them he won’t” and she left mad. She knows how I feel, but she doesn’t care. She has been giving him pills since he was a young child, only then she gave him Valium so he would go to bed early so she could stay up and party with her friends. I know this because my husband told me this. He and I are being honest with each other at last. I told him I don’t want her coming back to my home that she is not welcome. He and I have been going to a church together for a year now to try and find help through the Lord. But the devil keeps sending people in our lives trying to mess things up. And on top of all that, his mother came to our church this morning with the mother of a child of my husband’s, who she knows I can’t stand. She is trying to cause problems in my life. Plain and simple.

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