Support,
Using language such as finding a gf for you and your spouse as a couple, is the type of langauge that people will be quick to point out is not a good attitude to have. And in truth, they are correct because very rarely does a triad relationship work, at least not one where it can be successfully done by "looking" for a certain person.
It's technically not possible
The reason that it is impossible is because there is no way to predict the countless variables and cicurmstances that get thrown at the lives of people who are in any relationship. Some people believe there is nothing they cannot handle, and while that may be true, it's very rare. But it isn't about whether or not you can handle whatever cicrumstance life throws at you, the whole point is that in order to stay upright, so to speak, in order to "handle" all that life can throw at you requires "action" meaning you must do something to deal with it.
So the fact is that it is statistically impossible to create a personal add, find the unicorn, and have a triad that looks and feels anything like you desired before you met the person and began actually interacting.
So, to be clear, the two sides of the argument taking place on your thread is confusing and will never be sorted out because the two sides are talking about two different things, but we all won't cop to it.
You will not be able to theoretically "design" or dream up the way a true triad will be configured and work for you in your life. It requires so much flexibility with what actually has to happen, it is impossible to have it happen in a way that is acceptable for all parties involved. When you are talking about a triad that doesn't change -- in drastic ways -- at any point from the start, it doesn't happen. Because of this, 100% of the time the changes in the dynamic are not a relationship that all three will find as acceptable to continue.
THIS IS DEVASTATING TO ALL INVOLVED
it may quite possibly be the best way to throw two out of three people into dabilitating bouts of severe depression that cannot be cured by medication
For some reason, this cannot be foreseen by the unicorn nor the couple who hunt it. That is the jist of what some people are trying to make sure they did their best to at least warn you of what is going to happen
So going into it without looking for the "unicorn" which is by definition the hot bi babe that will love you both, be in a relationship with you both doesn't happen.
The reason that some people get so seemingly worked up about this topic is, that in virtually all cases, the details that a woman is willing to be the gf (the hard rules and guidelines that there is no breaking) is never what both spouses can accept as a married couple together. It really does always come down to only one knowing for sure that bottom line can be met, and one always finds out that the relationship as it stands is not something they can live with.
And it is a very destructive force in peoples lives
to be semantically correct, any relationship that works is a little more casual than most people accept for being poly.
They are technically correct
There is an unsolvable paradox that exists, the quickest way to explain it without highjackin your thread (which I have already passed that line long ago) is that NOBODY can have Love themselves and maintain respect for themselves when they are treated in ways by others that are not loving and not respectful. The only way a person can be in any relationship (it doesn't have to include sex, it can just be ANY relationship) you can only be in a close relationship with people who treat you with respect, people who honor your person, people who communicate Love in a language that you are capable of understanding.
Love is NOT a universal language that we all speak. The reality is at this point in time, it is much closer to each of US having our own unique and undecipherable to others, language that nobody that only ourselves is fluent in. It is NOT just a spoken and written language.
Love is a language that has so many different context and textures that include all the senses (sight, sound, taste, smell, touch) and it also includes concepts that todays psychology and the industry experts are oblivious to the very existence of because it is along the lines of things much less tangible and not measureable with instruments that quantify, so the emotional senses and all the different minute details that accurately define the Language of Love as it Is real, is not currently known by very many people. It isn't a book that can be written and even if it is, it is not one that should be sold for profit as at this point, humans in general are too stupid to not have the knowledge completely destroy Love on this planet forever.
Love is Nuclear, and despite what NASA would have you believe we are all stuck here until it is time to leave which is in no way in your control.
Love is potentially more dangerous and destructive than any bomb science can produce or any toxic poison that can pollute because Love in a much more comprehensive way that includes the spiritual component of it, when combined with the ignorance of the living, is capable of delivering final death, or THE END to an entire branch and often the entire tree of life in the greater scheme of things.
The is no "correct" way to do the right thing, the only way is to do it honestly, but nothing can be further from the truth than to use that fact as an excuse to live any way you want, as not living responsibly is the long and drawn out way to spiritual death, it's the road the world in currently on