Huh. Never thought of this before. Every time you have sex with someone, it changes you. It's a profound experience, and one that affects you deeply, and rewires your circuitry to a greater or lesser extent. I don't know if this is true for everybody, but it's certainly true for me. All experiences in life alter your thinking to some degree, but usually, after sex, I'm thinking about the world in a different way. 'Change' might not be the verb I want here, because I tend to believe that in terms of behavior and psychology, people really don't change.