How do I heal

My boyfriend and I have been together for 2 years. He used to look up an actress (naked for pleasure) from literally every tv show and movie he would watch. He had done this for years and I was not comfortable with it. He lied and continued for a year. He has now been free of that addiction for a year and promises he has not done it for the year. I can't get over it. I cant watch tv, movies or even the news without thinking about it and worrying. The trust is gone and I am so insecure. Otherwise our relationship is phenomenal. This is our only problem and it shouldn't be a problem anymore. He gets mad because I can't get over it and I hate feeling this way. I cant even leave the house and dont even want to go to counseling because I'm worried hes going to do it again. We are self employed together so we literally spend all our time together but when I have to leave for an amount of time I am so anxious.