Prior State of Residence and Marital misconduct and issues

We moved from out of state almost 3 years ago. There are many things that happened in that state that have had an impact on the state of our marriage and our pending divorce. It includes infidelity, alcohol treatment, alcohol and drug abuse, illicit and improper behavior, in short some bad messed up stuff. My STBX is telling me that her attorney told her that nothing that happened in the state of our former residence is admissable or usable in North Carolina in our divorce. I would like to show that her past behavior and track record DO have an impact on her wanting to get our child back, (Primary Custody), and that in the course of our marriage she is guilty of the very things she is accusing me of, and more. What is true? Thanks in advance.