What if you had a friend that told you about all this drama? What would you suggest to him/her?
IMO this is a very, very unstable situation for you, your W and your child. The law has been involved multiple times in a very, very serious way.
I understand you love your W for what she used to be. I think most of us can deeply relate to that feeling. But right now things are not how they "used to be" and unless you make some different choices nothing will change.
If your W chooses to continually engage in this highly destructive behavior, well, it's her choice. Your choice is to remove yourself from it fully.
I understand legal fees can be overwhelming but what else is there to do? IMO this is not a scenario where you can let things play out. It's simply too dangerous.
