You should seek a restraining order through the Family Court. A Family Court judge has the power to order him to stay out of the house, among other things. Feel free to call my office if you would like to discuss this in detail or if you would like help in court. Good luck.
I agree with the attorneys here. The house is an asset of the marriage and will be subject to equitable division between you. Whether he is entitled to half, more than half or less than half is an answer that requires consideration of more factors than have been provided here. As my colleagues have suggested, you should sit down with a family law attorney and discuss the situation in greater detail. Good luck.
The short answer is yes. Your mother is not immune from suit simply because of her relationship toward you.
However, there are a number of very important issues to weigh before taking legal action against your mother. These include but are not limited to the nature of the abuse, the effects of the abuse on you, the relationship between you and your mother, the relationship between you and other members of your family who may be affected by this, the likelihood of success and the extent...
Every state has laws of intestacy which govern situations like this. The property will pass according to the relevant state statutes. Likely, the individuals surviving spouse (if one) or children (if any) will take the majority of the property. If there is no spouse and no children, the individual's siblings, grandchildren or more distant relatives may be entitled to a share in the estate. You should contact a RI attorney to discuss the specifics.
There isn't enough information provided here to give you an honest answer. In any event, your best chance of defending yourself against these charges is by retaining an attorney. I would advise against posting any more information about this on the internet, or even referencing it on any public forum. Speak privately with an attorney.
If both parties agree that the outcome is fair, it is unlikely a judge will override their decision. If one or more attorneys are involved it's even less likely. I would have an attorney review the agreement for you and perhaps draft a property settlement agreement to be signed by each party. The attorney will be able to tell you if a judge is likely to allow it or not after reviewing the terms. Feel free to call my office if you'd like. Good luck.