Porn addiction

Hey guys, my wife saw that I had a porn addiction that was getting out of hand. My wife saw it on my phone one day coming in from walking the dogs in the morning, I can remember her crying in the living room, I was so confused. She ran into the bedroom and yelled you cheated on me! I was taken back by what she had said because I was in denial that it was cheating. I was sending pictures to other women online. I responded with yes, but I'm addicted. She was incredibly gracious and decided to stay with me and help me through. Today we are doing really well. The only issue is that I can't seem to get rid of the thought that she's going to leave me regardless of her saying she'll stay. I get scared that she's going out and cheating on me, she's never been a person to do these things tho. I just feel like I'm struggling to understand her level of forgiveness.