Originally Posted by SimpleSimian
Why, in a mono/poly relationship, does the monogamous person have to be the one who changes? Why can't the polyamorous person be the one to confront polyamory within themselves and teach themselves to be happy with the idea of spending their life with only one partner, circular logic included?
There is nothing that says such doesn't happen. Indeed, part of doing poly is that one negotiates how relationships develop--so poly folk can also negotiate a mono pairing.
I've done so. I've negotiated open relationships, poly relationships, and even a mono relationship or two.
There's absolutely no evidence that poly folks negotiate mono pairings in any lesser numbers than mono people negotiating nonmonogamous pairings (when adjusting for the lower numbers of poly folk in the population). It appears to me a large majority of poly folk were involved in mono pairings prior to actively identifying as poly--which means each of them negotiated mono pairings prior to actively doing poly.
So, poly folk have and still do negotiate mono pairings, though it's much less likely to happen once they step up as actively poly.
And I have to say I think this question is distant relation to asking why gay folks who have come out don't simply forsake their sexual preferences to remain with a hetero partner. A bi person coming out certainly could remain in a hetero pairing and negotiate a mono or nonmono relationship structure--and that may be the situation that fits best. The hetero partner isn't asked to become gay or bi to continue the relationship, so that partner doesn't have to change--it's the bi person who has to negotiate whether to live hetero or find a gay outlet, also.
So a poly person involved with a mono person is always the one who has to adjust the most. The mono person can always remain mono--tied to but a single partner. It's the poly person who has to decide and adjust to do a single relationship or do multiple relationships. Note that the poly person doesn't expect the mono person to suddenly desire to have multiple relationships, so isn't expecting the mono to suddenly become nonmono; your question discounts the fact that it is only the poly person who is required to change at all, from doing multiple ties to doing single ties.
I think that's the key concept. A mono person involved with a poly person can remain mono without any expectation of ever changing. It is always the poly person involved in those ties who would have to change.
It turns out your question is then based on a false premise--that a mono person would have to change when involved with a poly person. That's not the case. The mono can stay mono--it's only the poly who would have to change and do mono.