I've been reading this topic... and to be honest I haven't been sure what to say until now.
We are, at least to some extent, a product of our environment. The human mind works in many mysterious and weird ways.
I even think that my needs as an adult tie into my needs that weren't met when I was a child.
But there is one question that keeps coming back to me.
Why does it even matter. I'm not being flipplant or glib. I just speak as someone that was so busy for a period of over 10 years wondering "why"... that I forgot the "how".
I could tell you, indepth, the "why's" of many of the things that makes me who I am and what I like. I can even point directly to individual instances and follow the string of events from those instances.
And while I do think it's important to have some kind of basic knowledge of "why"... it's not nearly as important as setting it aside and dealing with the now. Some will argue that you have to know the "why" in order to deal with things. To be honest... I'm not so sure. Not beyond the basics at least.
After a while it becomes like picking at a wound.
I've spent a lot of time living in the past. And it wasn't understanding "why" things happened that brought me out of it. In fact it was delving into "why" for so long that put me into a state of near catatonia.
It was being exposed to healthy attitudes and having access to a supportive network of friends that pulled me out of my "why" stupor - helped me to face reality. Those are the things that helped me stand up and deal with myself.
It is entirely possible to be healthy and balanced and still have an interest in bdsm. With and without abuse in your past.
I don't know... to me it is only of minor importance what got you to where you are now. It's what you intend to do with it and where you want to take it from here that counts.
My $ .02