Will I be able to file civil case, liabile and slander from probate that was closed Nov.16

We were unmarried couple for 23 years. My "husband" passed away with no will. I took care of him for five years, he had cancer. Sister (PR) never liked me, left me totally out of his estate. He had a very successful business. Sister and brother divided estate 50/50 this not being his intention Iknow it has to be in writing, however he told me what he wanted, which of course I related to family. None of his family ever took care of him nor did even occasional visits. He would have NEVER done this to me and so many people know this to be true. Many untruths were stated in an emergency exparte injunction, . Accused me of stealing, forgery, among of few other things. I have suffered extreme emotional distress, depression, anxiety which has affected my life greatly. The loss of him, the accusations, threatening letter from sisters attorney, total disregard of our relationship. There are many other things that I question, sister has I believe perjured herself. Help please!