He has signed off from this marriage / relationship from you. Isn't it evident to you. He is there just to maintain his family status or kids. Only he knows. You need to accept it and stop going after him. You need to focus on you and rebuild your life than chasing a dead marriage. Consulting attorneys , they can sometimes help with private detectives and advice you on legal consequence of monitoring another person. You should be aware of the financial consequence. If you are ready to leave marriage you can proceed. If not its risky. Also, when a person is monitoring his/ her spouse, its a toxic relationship, its better to move on than chasing the unknown ( possible addition, affair, or anything else ) and hurt and loose yourself in this process. You are not helping yourself. Counselling/ therapy may help you. Focus on your career,growth, health and kids. I am not qualified to asses if your h is narcistic or not. But he dont have any love/ respect or empathy towards you. It will be better if you educate( watch youtube videos/ read about it) yourself on how to live with a narcistic person till you decide on your next step. Those approaches will give ideas on how to help youself in this situation.