An advice, no matter what others say to you ... but if you feel this weird and makes not more sense for you, probably you should listen to yourself.
I have seen many good people get hurt because they are so obsess with a person that want to give poly a try even if they feel it is not their cup of tea. After they realize they should had heard their "inner voice" and get the heck out of it.
This is not for everyone and even how good it is for some of us, nobody has a right to chose for other person ... so put your thinking hat and see if you could possible handle all the situations that come, what if the other person tomorrow is a guy? Would you be able to manage jealousy issues? It may be tougher than to see your girl kissing another girl.
What I am trying to say is, contrary to what many believe, I think we are not here to "convert" others or be converted ... if this is not what you see yourself doing, move on. Best wishes for you to make YOUR very best decision!