Dominance, the mind set

I've been wondering what motivates a Dom like Z--or K(the new guy) who isn't a sadist, doesn't want to hurt women, but is very much a Dom.
Themes that emerged from listening--and talking--are about sexual and emotional control, the pleasure of controlling a woman and having her submit to you and do what you want, even--or sometimes especially if--it is embarrassing, painful, or pushes her limits in some way.
I asked Z if this was accurate and he said yes.
I then asked him if part of the sexual energy was a means to control a woman and bring her under the Dom's control.
He said yes, absolutely.
(Makes sense)
We then tried to talk about the hard to define edge between this kind of intense emotional/physical play and the deeper meaning that is has--Z and I are equals, but at some point when we begin to touch, things change and we move into these roles--he is the Dominant, I am the Submissive.
He orders and controls, I fulfill and obey.
In my submission is incredible power and amazing sexual thrill.
In his Dominance, the same.
And under it all, a growing shared bond of closeness, caring, lust, passion.
(How could anyone NOT want to experience this?)

In some ways, this D/s relationship is the most incredible thing that has happened to me in many years, and yet, there are moments, as Z said, when I must ask myself if I have gone insane..and then I agree that I have, but in such a good way...