I Am Having Problems Dealing With His Ex-wife Or Ex-girlfriend

She wasn't even his gf but just a fwb and magically assumed she had been in a relationship with him when my bf and I announced we were together. Of course she called me names and claimed how much better she was then I. Always bombarded him with messages just going off for weeks... well now this chicka after her last messaging fiasco with my bf and he told her where to go and how to get there... all of a sudden the ministry called the next day in regards to his son they said someone had called accusing him of drinking 24 beers and neglecting the child and passing out on a regular basis. We can only assume it was that crazy chick trying to get back at him. This is a bit much ugh. I don't even know what to do about this nutcase.
Like move on and leave us alone.