After many years of plaintive pleading to my wife that she participate in my bondage and c.p., it finally occurred to me my approach was all wrong, at least for my wife's psyche. However I had planned, hoped, pleaded, it was understood as laying a guilt trip on her that she wouldn't do this for me, and so she resisted. I suspect that was indeed a large part of my approach.
At any rate, about 8 years ago, or so, I let up on the cajoling and pleading. And she responded, slowly to be sure, but still positively.