Repeated sexting outside marriage.

Hi, I have been married for last 3.5 yrs. It is a love marriage. Since we got married, both of us have been keeping very busy doing lot of stuff to build our career and that has taken a toll on our sex life. Somewhere both of us had given up on each other to correct it. But recently we confronted each other and resolved to work on improving it. With this background, my wife has caught me 3 times sexting someone and the entire experience has been traumatic for both. I love her a lot and i am aware of the consequences but it becomes very difficult to resist the urge not to do it when the opportunity comes. I resist it for some time and then eventually give in. I have apologised previously and asked for 1 more chance everytime but this time my wife wants me to consult an expert to see if there is a problem. I want to get this resolved and so seeking help inspite of being terrified to share these things.