best friend problems

Okay so my best friend has been on and off about leaving her husband, and she wants nothing to do with him, she wants to be able to live in the house he just bought for them two and their daughter and she wants him to give her money, but she has been for the past couple of weeks sleeping at her mom and her "drug dealing bf" which she is an idiot! And bringing her daughter around him and when her husband is off she is constantly away from him, she comes over to my house everyday and I am 8 months pregnant , sick and have two kids in school. I have my family on a strict schedule and it's important to me to keep it that way. Well she comes over everyday and I'm sick of it I keep trying to tell her she can't just keep coming over all the time especially because we live with my MIL. And she doesn't get it. Also her two year old daughter is a brat from hell and pull my kids hair slap and scratches and always steals my kids toys! And she does nothing about it and quit frankly I'm starting to loose my patience. How do I tell her nicely I don't want her coming over any more?????