Omgoodness my mil

So long story short, her oldest daughter's husband was openly cheating on her, everybody said to leave but my mother in Law told her to stay. Fast forward 6 months and now she's ( mil) telling everybody it's a horrible situation and we're going to lose her. And what a horrible person the husband is and on and on and on. Telling my husband what he needs to do about it. All the time I'm listening and about to bust open and scream at her "Oh my gosh shut your trap. You fucking TOLD her to stay, you TOLD her to continue to live with him and allow that stuff, to not stand up for yourself. So how about you stand up and pat yourself on the back. What a horrible excuse." But i don't. If we're in the same room, I politely excuse myself, if we're on the phone, I find an excuse to get going. I can't handle it.

I should add, the daughter is nearly 40. And now she's asking my husband to step in and fix it all, as the younger brother. She's ALWAYS given horrible advice to her kids then been all dramatic when it all plays out exactly as we all knew it would.

I think she needs the drama in her life.