I tend to think not. In our natural state I think we are pack animals (tribal people). As a species I think there is no problem with us swapping partners. I believe we are serial monogamous creatures. We fall in love, listen to all the dumb stories, get bored after a few years and look for new person to tell our stories to. Perhaps it is our artificial life expectancy that makes us serial mates. If we died at 30 we might be considered generally monogamous.