Gore Vidal said, “I never miss a chance to have sex or appear on television.”
But Tom Robbins comes back with, “…while sex without love could have its thrills and satisfactions, sex without soul was like salad without dressing—a bowl of roughage fit for cattle and goats.”
The moment sex ends, you get a moment of clarity about what you are looking for. No longer are you driven by your dick, but by the heart and the rational mind. If you don’t really like the girl you’re with, you end up fleeing the scene.
Maybe Ben Stiller did have the right idea in 'Something About Mary'