Gabe, I've written and rewritten a response to your last post. I'm just gonna post the common theme:
As long as your son is safe with her, then her personal life is none of your business. I know it sounds harsh, and it ticked me off when a good friend told me the same. But, it is true and as soon as I understood that and started respecting her privacy, it got alot easier for me.
I hope this helps you get to where you need to go. I know it helped me.