quote:
I have a sister in law that seems to get in fights a lot with people including other family members.
When she does, she expects my wife and my kids to take her side which means they cannot talk to, or see, the people she is fighting with or else she gets mad at them.

I told my wife to stop fighting her battles. We don’t know the details of her issues with other people so we can’t be expected to be involved. I wouldn’t ask the same if I were fighting with someone.

So there is a new years eve party coming up at a friend’s house and we’re invited but she isn’t- because she is fighting with the wife. She expects us not to go and has made it a big deal. She says that the party hosts are bad people. She says they hate us and that the wife has cheated on her husband and flirts with sister in laws husband.
If we go, she has said that she’ll reveal a secret that she thinks will hurt us. Not sure what it is. I told my wife to let her do it. No one will believe her anyway. My wife doesn’t want to lose her sister and wants to stay home or go out elsewhere.

I really don’t need advice here but feel free to give it. This is just a burden that I have to deal with. I know that eventually, once my wife stands up to her and lets her fight her own battles, it’ll all take care of itself. Just have to weather the storm.

I want to go to this party though.
I’ll probably confront sister in law ... again... and tell her to find a cliff and jump off. Will revert with results

It sounds like you and your wife need to come to an understanding that her sister is fricking toxic and that she's bringing unnecessary stress into your lives.

This isn't cancer. It's not that she's in the OR facing some life-changing surgery. She didn't lose a child to these people (or any of the others she gets all of you to side with her against).

The problem is her and her attitude of scorched earth for any slight. She has the conflict resolution ability of a child.

You need to work on your wife, to get her to agree that her sister needs help. If/when you get to that point then you tell the sister that you're worried for her and how she reacts isn't healthy.

If she listens and takes it to heart, help her find counselling and you all win.

If she takes offense to the point where you are now the enemy then you two just shut her out until she cools the frick off. When she comes back, make sure to establish boundaries by telling her that not only do you still believe she needs help but that her reaction just underscored it. You and your wife win some peace from this.

The bottom line is that your sister-in-law needs help and no one can help her but her. All you and your wife are doing by being amenable to her are enabling her by supporting her juvenile approach to others.

Good luck.