Just something I've thought about recently after a discussion.

The Relationship Spectrum could be the most accurate way to understand all forms of relationships in a society that practices Compulsory Monogamy. By assuming Monogamy as the norm, we skew the conversation everything outside of Monogamy as being nonmonogamy instead of recognizing all of it as being different parts of a greater experience.

It's like looking at a rainbow and thinking "look at all that non-blue". While it's technically correct, 'non-blue' applies to red, white and green equally when those 3 have nothing in common except not being blue. If all your focused on is blue then this is fine but if you're looking for any other color, 'non-blue' isn't very useful.

Theoretically, Monogamy is on one extreme of the spectrum. It is just short of abstinence, celibacy, and asexuality. It is by design a limited, narrow definition of romantic relationships and idealizes lifelong marriage commitments.

On the other hand, polyamorous dynamics would be the other end. These are relationship styles defined by commitments to multiple people or the lack of those exclusive commitments. Freedom and happiness can take priority over longevity or dependency.

By thinking of Relationships along the Relationship Spectrum, not as Monogamy vs Everyone Else, we can better understand how comfortable people are in various commitments.

My example of the Spectrum:

Celibacy/Abstinence: The avoidance of all sexual or romantic attachments.

Monogamy: Exclusive Emotional, physical, and sexual commitment to one person.

Swinging: Emotional commitments to one person with agreed upon sexual Relationships with others who generally have similar commitments. For example, couples who swap or seek out "Unicorns".

Polyfidelity: Closed Relationship dynamics that involve more than 2 parties with agreed upon commitments. For example, triads, closed polycules, and "polygamy".

Open Relationships: A relationship that puts little restriction on the amount of additional partners. Typically a central couple that is openly available to others as individuals. The degree of Emotional investment can be negotiated by involved parties.

Polyamory: Relationships that involve more than two parties consenting two a variety of dynamics. Communication, consent, and autonomy take priority as dynamics, partners, and boundaries can change.

Solo-poly: An individual that seeks out multiple romantic relationships with no intention on enmeshed livelihoods, finances, or status.