I suspect my mother in law is sabotaging my relationship with my husband. She's very two faced and likes to twist everything I say. But she's very nice in front of me. What should I do?

I know how you feel :( recently there was a heated discussion over me keeping my name after marriage and she was not pleased. I told her it will be an administrative nightmare to change my name and that it can cost a lot. She chose to ignore that part and started with the emotional guilt tripping. This happened at a dinner party where there were other guests. I just smiled the whole way through and complained to my partner after. He offered to talk to his mother for me but I told him, if it happens again (which I know it will), I'd confront her for it. She was never like this before, dunno what changed but I reckon it's alot to do with the possibility of me and my partner uprooting and moving away after the wedding. I always try to be the classy one and let things slide but I'm close to the boiling point haha. Before that happens, I hope that I get to air my opinions civilly.