YOU ARE WRONG! WRONG! WRONG!
My wife and I too became less intimate as time went by and I too rationalized seeing providers as having needs met without any chance of an emotional entanglement. I even convinced myself I was doing my wife a FAVOR by doing this and by not pestering her with my needs. Well, I'm the biggest idiot in the world and you, my friend, are right behind me. If you truly love your wife, you will stop and stop now. Do you realize how much she is going to be hurt? Do you really think she is going to say "Thank you darling for doing that'? REALLY???? And how about your kids. How old are they?
My wife filed for divorce the very next day after discovering my escapades, and here we are 3 years later and I've not once had the opportunity to explain any of it. My step-daughter and son have not spoken to me once in these 3 years since even though I send e-mails weekly. My step-daughter has had a child during this time and do you think I get to be involved? Not hardly. So, here I am, after 25 years of marriage divorced, alone, with no family. Like I said, I too loved my wife with all my heart. She was the only relationship I ever had. Just yesterday I was told she has remarried and I just want to kick myself. She was a great wife and even better mother and will be a fantastic grandmother. Too bad I'll never get to see her face light up again.
So take a long look in the mirror and ask yourself....why am I doing this? I suggest you simply confront (not angrily of course) her and work it out with her. You are on a bad path and you will be found out eventually.