HD,
It's time to come clean.

You need to say to her: W, I have not been honest with you. I am sorry for that but from now on, I want to be honest regardless of what the fallout will be. I have been acting as if I was content with the status quo, leading you to believe that things can continue the way they have been. This is not fair to you, as my internal feelings are anything but content. I need for things to change or I doubt I will be able to stay in this marriage--I cannot compromise my integrity and stay happy. Sex is important to me and, I believe, an important part of marriage. If we can't come to an agreement about it, I doubt we will be retiring to WI. I am sorry if this comes as a shock to you, that was never my intention to blindside you. I am finally at a point where I am willing to say 'this is who I am and I hope you want to take part in me'. "

Good luck, friend! We are all pulling for you.