Dealing with an Ex

Ok, so I have been contemplating writing anything about my ex husband having a "friend" as he calls her and my girls having contact with her. I have so much anger still towards him that I don't think that he deserves anyone or anything. For those of you that don't know, I was married for 7 years to him and he had an affair with his boss. I also found a list of several escort phone numbers in the garage under his tools when I was packing to move out of the house. I am just appauled that he would even have the nerve to ask me if she can come with him to Katelyns birthday party Saturday at my house! OH NO HE DIDN'T! He then prompts to ask me if Katelyn can go with him over to his "friends" house on Thursday night and spend the night with him there and she will watch her on Friday......I have never met this lady......what is she is a child molester, or someone in her family is that visits, or lives by one, what if she does not watch her good and someone kidnaps her.....all of this is running through my head. In case ya'll are wondering where Ashleigh is, she doesn't like going over to her dad's house. I think Ashleigh has alot of issues with him, she remembers everything we went through when I was going through my divorce. I have always told my girls that if they get a stepmom that she will be like the stepmom in Cinderella, lol, I know ,I know, kind of mean. But, he brought all of this upon himself. Well I said Yes this lady could come Saturday to my house to Katelyn's party, but I am not looking forward to it. Why can't he just run away and never come back????? My life would be so much easier. Ok. I feel better now. Any suggestions???Any? I am at a loss!