N, I'm sorry that you had to hear such comments by your xSIL. I don't know what she was thinking or hoping to accomplish by telling you such things. That is mean and hurtful. She should have kept those comments under her roof and not told you about them. Yes, you are still communicating w/her, but the conversations need to be kept above the MLC level. You need to remember that a dog that brings a bone will carry one. You just don't know what she carries back to her h.
From what I've read this morning, it sounds like the ow is a gold digger and is out only for money. Little does she know, there may not be any left when he's completed his walk through his crisis. As for your h, you wouldn't want him back in your life right now the way he is. You are far too good of a person to have to put up w/his nonsense, the ow and your xSIL telling you about the conversations.
In the future, try to keep the conversations light and airy, no talk of what they are doing. The less you talk about it, the less you'll hear about all of the ugly details. He will have to pay a very high price be it here or earth or the after world.
Please take care of yourself, keep the focus on you and your family. Try to enjoy your time w/your family.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.