"Sexual dysfunction often plays a key role in risk management by couples over time. It seems crucial not to get too excited about the other, and diminished excitement serves the purposes at once of self-protection and revenge. I was once excited about you, the diminished arousal seems to be expressing, but there is not much to get excited about now. Often lovers work together to pretend they are safer (even if also a bit sadder) over time, by collapsing their expectations of each other in collusively arranged, choreographed routine. Each feels the other is less exciting because of being so familiar and predictable. And each acts towards the other in as wholly and artificially predictable a fashion as possible. But, of course, lowering expectations also empties out passion. No risk, no gain."