Mother in law started a smear campaign

What do you do when your Mother in law has talked negatively about you to the rest of the family? I’ve had a wonderful relationship with every member of the family for 12 years. But recently, my mother in law crossed some boundaries and caused my husband and I to confront her about her controlling and manipulative behavior. We were very kind in our delivery, but she cried, got extremely upset and turned the whole family against me. How do I move on from this? Has anyone else been through this before? This makes me want to never speak to her again.