OP, I am in awe that you can recognize and abhor this behavior from your own brother. I was married to an abuser and even though his entire family knew he had problems, they also took his side and continue to try to make it look like it's my fault (all charges led by him, of course). You acknowledging this to SIL and showing her that, despite your family ties, you are HER ally, is tremendous. I hope it will show her that she has a way out; that she's not crazy; that other people who love him see it too.

How awesome is family that loves! Thank you for being there for your family. A safe haven for all with protected boundaries is real important! If this were my loved one, I would try to get her to change her thinking and replace negative with positive. Little by little, minute by minute, the good thoughts will take over. Thinking is believing and believing is what we are living and doing. I would tell her this is a work in progress, and she can begin by changing her thinking, then seek help and guidance. Begin the process and believe!

As someone in this situation I can tell you no one on the outside really knows what happens in our house. It's embarrassing that it happened to me, I don't want people to know so I cut myself off from my friends. I am successful and a strong woman and if you met me or my husband you would have no idea. The best thing I can say is to be there for her, be her friend for lunch and coffee. Offer to take her kids out so she has a moment to herself without her spouse because otherwise she is probably always on edge not knowing when the next blow up will be - could it be when he is alone with the kids?. Be close to her even when she is closing you off because if things are bad there will come a time when she wants to call someone and tell them something is wrong or that she needs help.

OP here. Thanks for all your outreach and insight into what's happening. I really appreciate it. And I'm so glad you are not subject to that anymore.

I think/hope the court cases will end up mandating some sort of therapy or substance abuse assessment/treatment for my brother, which may help. I will let her know, no matter what, I support her.

My sister was too embarrassed to tell anyone. She's a strong woman, who never puts up with BS. The breaking point was when he gave her a black eye and she had to go to work looking like a DV victim. Holding her at gunpoint for any entire night wasn't enough, but the black eye threw her over the edge.

I think her strength was part of the problem. She thought she could handle it. He got upset sometimes, but if she just changed her behavior a little bit, she could get back that guy she was infatuated with. The problem is that guy was only a mirage. The abusive asshole was the real him.