You mention your wife's sister before. I would talk to her in private and tell her what your W told you on this suicide infusion. To tell the truth it's very hard to take it as she is playing victim or if she is so lost she can do some crazy.
It will be hard for you to get involved, you don't know what is exactly the involvement she has with this OM, and you want to cover your end and not be blamed for any unfortunate accident.
I think that family can get involved and try to help her at least to see a doctor and a IC, for her own good. There is also a possibility of you playing your cards now, you can say to her that if she is so psychological unbalanced that you will be forced to ask her to put some distance with the kids, so do not hurt them further.
You can find a polite way to put it to her as looking for the best interest of the children, that is also her best interest. You can choose the words to say that if she gets help then she will be welcome to visit her children but until then she will need to limit contact.
I know she will feel like in a corner, so since you know her, you will need to find a way to approach the subject in a way that she will see you care and that's why you will be doing this.
By other hand, if she faces to go to an IC then maybe she will slowly realize that she is destroying her life over some foolish OM with his alcoholic demons. There is nothing wrong to be an alcoholic and get help and get better and all that. But it seems that this guy is not in a hurry to get better.
As you write here on this board, we are seeing the signs on your kids. It's been long, and for teenagers it feels even longer, they are being dragged into this nightmare, the pain, the mom that abandoned them. Kids are not stupid, they know what she is doing. They can't resolve anything, they can just hurt and eventually they will start acting up on this.
I know you are doing your best do hold your family in a peaceful environment, but you can do just as much as one end of the spectrum. Please, talk to your IC and seek advice in what is better for your teenagers. It's a very difficult age and you don't want to damage them to the point you will need to deal with other kind of problems.
I also know we all get involved in doing the DBing process, but there is also a part of it that is to seek what is better for yourself and your family. Sometimes we need to go through some harsh realities, even if we do not want to, but we need to protect the ones that can't on their own yet, the ones we love the most.
I would like you to stop for a minute and do a analyze all what is going on. All the pros and cons of your W's behavior and how it is affecting your kids and even you.
Time to step up RD, there will be no man or woman that is more important then the ones you need to take care off.
I will always be here to talk to you. I have made my decision, I will take good care after my children no matter what. My H is important and I love him with all my heart, but he decided to follow a different path and I can't control what bull he is doing right now.
Be well RD, you and your kids are in my prayers. I love you and wish all the best for you.
