For some time I have been somewhat of a scholar on the matter of sex and the miriyad of related issues. I have always wanted as much to know Why as I have wanted to clarify How and Who
So I proceeded to Read... Verociously and in great volume!
Some of the key questions I have in terms of our relationship specifically, was the question of a) why swinging does amazing things for certain marriages and why it kills others, and b) the psychology of voyerism, as I don't "get" why that is a turn on, even if I don't mind participating.
I recently finished reading a short but fascinating book which answered, very clearly, some of my questions, I highly recommend How to think more about sex, by Alain de Botton
It was great, easy reading and I was enthralled by the window into the psychology of sex and "deviance" which it offered.
Great stuff!