What does “weirdly” mean? I would say that we often behave differently. I can’t speak for all men, but I can say that sex often doesn’t turn out as good as we imagine it to be. I would be remiss if I failed to mention: women frequently behave “differently” after sex. The sex isn’t as good as they imagine it’s going to be, or sometimes the man isn’t ready to be in a committed relationship right away. And then there’s the effect of hormones. After the ejaculation, our hormones return to normal. And it’s difficult to fight chemistry.