The biggest error and misinterpretation of any information regarding monogamy/non-monogamy and human nature is the injection of genralization and the lack of broader studies.
No one can speak for all humans. Some are monogamous and happy, others are non-monogamous and happy.
Helen Fisher is one of the most accomplished and published biological anthropologists. She is also one of the most published scientists in the area of human love. But again, she offers her research as not "the only way". Her brain mapping research is in depth and very widely recognized. If you want to know about love in the modern age I highly suggest to look at her research.
Playing the Game of Life with Monopoly rules.
Monogamy might just be in my genes
Poly Events All Over