Pleasure, the other side of Pain

Being in Love and getting your heartbroken (pain) are often two sides of the same coin. The feelings are the same. One feels like they are dropping into depths so deep its hard to capture into words.Is this why our society has been so captured by the Fifty Shades of Grey novels? Did E.L James bring out the obvious? or was she reminding us of the primal needs we all have of love at some deep level?Do we all secretly wish we had our own "Christians and Ana's?" People balk at the whole mention of BDSM - the whole notion [...]