Ex wife makes me crazy

[clannom31]

I'm hoping someone can give me advice on how to deal with my husbands ex wife and her family. I have been with my husband for 7 years and married for 5. Since around our 6 month point his ex wife has been personally attacking me in one way or another. Over the last 7 years she has forced his 2 children to lie to police and state social workers about me abusing them. To date it has been a total of 4 times. Each time a sheriif was sent to my home and a social worker investigated the claims. In the end all of the claims were unfounded and the children admitted being forced to lie. One sheriffs officer even informed her that she was only doing this out of jealousy and if she continued I could charge her with harrasement. In 2003 she physically assualted me but no charges were filed because I defended myself during the attack. Then in July of 2007 his 2 kids came to stay with us for 2 weeks and his 11 year old daughter informed me she had been sexually assualted by her 2 teenage cousins. She informed me that when she told her mom and grandma they laughed at her and left her alone with the boys anyhow. Trying to do the right thing to protect a child I reported the abuse to the local police and protective services. His ex wife admitted to the abuse and said she her daughter had informed her of the incidents. So for the last 11 months his children have been in our custody. Recently their daughter recanted her story and informed us she had lied about it because she was angry with her mother and wanted to live here. Now it's been about a week she's been back with her mother and they are once again accusing me of abuse. The ex wife, her mother, and his kids are saying not only did I cause the children physical harm but I knew the daughter was lying and threatened her to continue lying. His ex wife has now called my childrens school to question them about the alleged abuse, the local Child protective services and law enforcement. They are constantly calling my home and my husbands cell phone to say these things and harrass us. I have never abused his children or even spanked his children. I have been harrassed, attacked, physically threatened, and put through hell for the last 7 years. She even had her son try to knock over our wedding cake and dump red punch on my dress. She uses the kids to constantly relay messages to me and cause me emotional and physical harm. I want to know if I can file a lawsuit for harrassment and defamation of character against this woman to get her to stop.