I’m in a a bit of a situation

I’m gonna start by saying that I love my wife. This situation happened little over a a year ago now and my wife went to our trip and on our way back home We had an argument things got rocky and we got an upset argument over how I wanted more sexual activity because I was not receiving any for months on end, things got rough and we almost ended things about a week or two later when we got back home. And I lied on Snapchat and asked a random girl for a nude while I was in the mood I had no intention on sending back to her any photos and I don’t believe she sent me any but I did ask for a picture while still in a relationship. I know I should bring this up to my wife and talk to her, but I’m not sure how I should bring this up. It has been tearing me apart the fact that I went and asked for a picture from someone else, there has been many restless nights and constant thinking about what her reaction might be. What should I do?