Sorry for the bluntness, but you are not purchasing a puppy. This "girlfriend" also has needs, goals, family, baggage, a life... Please put this into perspective and realize that people are not owned and cannot be pushed into "loving" and having sex with people after you decide they are okay. That they match up. Its very disrespectful and creates lack of worth for partners. This fantasy woman deserves to be loved and cherished equally to you. She is worth as much as you are. She is not your slave that will obey what you tell her.
I suggest you work on getting your head around him having another girlfriend and stay out of the triad situation. No one deserves a partnership that is made out of pleasing a man. What is more healthy is creating situations and relationships that are fulfilling the needs of everyone involved. If you know you are not going to be okay with this then I suggest moving on to someone that is like minded to you or working really hard on that jealousy and doing the work that needs to be done with him to make this work. It does work. It is possible, but it will rock your world and nothing will be the same again. Most of all your relationship will never be the same again.
I suggest you have a look around here. Read lots and get to know what poly is. You seem to not have a grasp on the basic concepts and theories. Have a look at the search engine in the tag section and find threads that seem interesting. You might want to start with "unicorns" "unicorn" "triad" "vee" "lessons" "foundation" I would also suggest getting your boyfriend to read and learn with you before looking at any "girlfriend" options.
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