I found some studies and articles on the topic of AF/BB, the idea that women classify men in two categories: the ones they want for sex and the ones they want for cohabitation.

[Sexually unrestricted women display more distinctive short-term and long-term preferences. Good genes for short flings, good dads for long-term.] (http://www.psypost.org/2018/06/sexually-unrestricted-women-distinctive-short-long-term-mate-preferences-51349)

[Ovulating women prefer masculine “alpha” men, non-ovulating women prefer more feminine men.] (http://www.sscnet.ucla.edu/comm/haselton/unify_uploads/files/gildersleeve%20et%20al.%20sex%20roles%202013.pdf )

[A look at women's different sexual choices depending on ovulation.] (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1559901/)

[Women's sexual strategies: the evolution of long-term bonds and extrapair sex.] (http://pillse.bol.ucla.edu/Publications/Pillsworth&Haselton_ARSR.pdf)

Then there's these articles (both by female therapist and author Esther Perel):

[The traits that make a man a good short-term fling and a good long-term partner are incompatible.] (https://blog.mindvalley.com/lessons-about-relationships-from-esther-perel/)

[Women express what they sexually desire through affairs, not relationships.] (https://www.lennyletter.com/story/want-to-know-what-women-want-ask-them-about-their-affairs)

There's a few quotes that are worth pointing out:

"Passion and security can not exist at the same time."

"Our desire is nothing else but an intense longing towards something or somebody we see from a distance. If that somebody is always present in our lives, we might need to walk a few steps away."

"If it were true that women's sexuality is primarily dependent on relational connectedness — love, commitment, and security — then shouldn't sex be thriving in loving, committed relationships? But too often, it's not."

"Research shows that men remain sexually interested in their partners for longer, with the decline of desire happening gradually. Women tend to lose their interest in a shorter amount of time and rather precipitously."

This one's important: "Women often seek commitment because it's the ultimate affirmation — to be chosen above all others. But ironically, once the commitment is made, the equation shifts."

I think there are a few particularly important lessons for people but specially for men: