Originally Posted by Athena
Monogamy implies that we can have only one true match and that we are only capable of truly and fully loving one person, and there is a schema that two people marry and establish a unit.
Since I am a student of early Judaism and Christianity, I will add that a primary pair bond developed out of the patriarchy, whereby men owned women, and needed to control "their" women's fertility to ensure they left their other possessions to their own biological offspring only.
Of course, polygyny was common, allowed and practiced BCE (and still is practiced in some Jewish and Muslim communities to this day).
Monogamism developed out of an idea of St Paul's that a Christian bishop should be the husband of just one wife, to ensure he didn't spread himself too thin, and have plenty of time left in the day to focus on God and his church group. This was later extrapolated out into the general public.
Unless you believe St Paul was a true prophet of YHWH, you'll see that his ruling about one man/one woman went against what his Jewish ancestors were doing, with God's apparent blessing, back in the day. YHWH's greatest prophets and heroes all had multiple wives, and still had plenty of time to hear the lord and do his bidding.
There is also evidence in the Bible that not only did Jewish men have multiple wives, temple "prostitutes", aka holy ones, of both genders, lived and practiced in the Jewish Temple. Also, orgies at certain holidays were an approved practice (even in the Temple courts!). I have no doubt women also had female lovers, but this isn't mentioned in the Bible, because lesbian sex can't cause pregnancy, and therefore doesn't count.