KB, I don't like what you're describing about your W, I see some red flags in her behavior. She's being abusive. She's already escalated her abuse from verbal to throwing things which is usually the precursor to physical violence. Please be ready to protect yourself and your son. If she so much as raises her voice I would immediately put her on notice that you will not tolerate it. Calmly tell her that based on her out-of-control behavior from the other night, that you are very concerned for the safety of yourself and your S and if she shows any signs of violence then you will immediately call the police and have her removed. If she continues to escalate then CALL THE POLICE. This is setting a boundary, and a boundary must have consequences or it's worthless.