Brother’s (M47) wife (F45) causing issues.

Throwaway.
My brother’s (M47) wife (F45) is causing issues.
For context a number of years ago my family caused all sorts of trouble for me (M38) and my now wife (F37) to the point where we had to long distance for a period. We got through that, got married and had kids. Brother and his wife have kids also similar age.
For context his wife was one of the main issues and is incredibly entitled herself, but for peace and the kids we made amends.
A few weeks ago my Brother’s wife started blanking my wife – now this is how things started a few years ago so triggered a lot of things. We asked her what was wrong, she said nothing and continued the blank and act as though something was up.
A few days ago she tried to poach our babysitter for herself out of the blue. For further context she has successfully pissed off every babysitter she has had in the past. I got upset because she’s going on a certain way and this comes out of the blue. When I spoke to my brother a few weeks ago about my worries he didn’t want to know, so I messaged her directly this time.
That triggered a reaction where I spoke to my brother face to face, and he made it out as though all of this was my fault and it was my responsibility to repair this, despite him unwittingly revealing that some of the information his wife fed him was lies. I spoke to them about historic events and he minimised it.
I came away from the meet up with a desire for things to be right and peace for the kids, but not where I have to kiss my Brother’s wife’s ass. I’m fucking furious about it and feel gaslit by this DARVO situation.
Anyone else went through similar? How did you handle it?

Tl;dr. Entitled sister in law causing issues. I confronted. Now I’m DARVO situation. Anyone else had similar and any tips to deal with please?