General response to the thread:
I'm quite uncertain how being mono- or poly- relates to, say, being hetero-, homo- or bi-..., in the sense of what are commonly called "orientations". People are generally understood not to change their sexual orientation (so-called). Yet many people do change their orientation with regard to poly- or mono- over time -- usually from mono- to poly, I suspect.
I'm a bi- guy (with lots more experience with men than women) who shifted over time from mono- to poly, and I experienced this shift largely as a sort of shaking off of some very deep-rooted socialization in what might be called "mandatory monogamy". That is, early on I bought into the premise that if it is love it is sexually and "romantically" exclusive --, and everything else is "just lust," not love. (The premise being that true [romantic] love is exclusive.) I was also trained to think of promiscuity as ugly and inferior to non-promiscuity -- but these are apples and oranges, though related.
So..., I'm finding it difficult to try to think about poly- and mono- as "orientations" because of the strong taboo against poly- and the near ubiquitous expectation that "good" people be monogamous. (With the premise being that not-so-good people, or bad people, are non-monogamous.)
Polyamory is probably generally "pathologized" in our culture, just has homosexuality had/has long been. It can only begin to become understood as an "orientation" when it is de-pathologized -- accepted as just one among a spectrum of "normal" human orientations.
And so it is with monogamy--, which is the point I've been setting up. What does it mean to say "I am mono-"? Is one expressing a quasi-permanant orientation in such a definition of one's self? Very likely, not. That is, millions and millions of people will discover at some point that while they thought they were permanently mono- ..., well, they are not. The social conditioning and taboo encourages folks to define as "normal" (and thus non-pathological). And poly- is not yet widely accepted as a "normal" option.