The others have given good advice. This reads like an entire chapter in the novel called my poly life. Only I was in your girlfriend's position, and I was the one who wanted to start a family with my husband. These are some of my mistakes when it came to this. Please learn from them.
I did not check in with my ex about my maternal desires. The urge to become a mum was strong enough to override any objections she would have had or any love we shared. I wanted to have a child with my husband, and I was going to do it. If she had told me she was not okay with it, I would have opened the door and let her walk on out. Honestly? It was not something I wanted to discuss with people including her. At that point, we had been together for eight years. It was a private matter between my husband and myself. We wanted to keep it between us. I told her that I was going to have my implant removed in the hopes of conceiving. I did not desire her sexually during that time, but we were going at it like rabbits. The only difference is she was not in our home when it happened.
I invited her to be part of the prenatal care and at the hospital during the deliver. She was not in the room because I did not want her in the room. Our therapist believes the invitation to her was out of guilt, obligation, and the lack of romantic love towards her. Like I was compensating. This is going to sound bad, but I did not want her to touch me during my first pregnancy, so we had a non-sexual relationship. (Sex was off-limits due to bed rest during the second pregnancy, but I had no desire for her then either.) The sex with her did not resume after I delivered either time, and it was not happening very often once I settled in to being a mum both times. My libido was far too wonky afterwards, and I was more worried about taking care of my children and nursing them than being with her. It seemed normal that my desire never returned for her. After a point, it just stopped altogether.
I had my first child in December of that year and second child last year, and honestly, my therapist has deduced that my heart stopped being in the relationship with the conception of my first child/subsequent falling in love with her and the overflow of love I was feeling towards my husband over the life we had created. It saddened me to hear a therapist telling me that and hearing something similar from my mum a couple of days ago.
Have you asked her if she sees this as being long-term? Have you brought it to her attention that you are not feeling like an equal or primary or whatever? Have you found out what role you are going to play in the baby's life? Are you even going to be part of his/her life? It is said that one person always loves the other person more than they love them..
I saw that you said something about moving in and with them. My strong advice? Do not do it. Especially if you do not want children. You can be happy for her, but it is a lot being around children all the time. You do not want them to get the idea in their heads that they have a girlfriend/play partner and live-in babysitter. If you think that moving will give you more opportunities or desire a change of scenery, do it for that reason. I would never move for a person unless I knew I would love the place. Move in to your own place and gradually increase the frequency of how much you stay at their place or visit however much is possible. If it seems like you are getting on well, try it then, but make sure you do not dig yourself in a financial hole. Have a little nest egg in case you realise that cohabitating will not work. There is nothing like having your own place. Some people are just not cut out to live together.
I implore you to talk to both of them but be sensitive and honest. It is okay to have and discuss your feelings, and I hate that bullshit about having to work on yourself all by your lonesome. Grates on my nerves royally. It is still early on, and this is your first poly experience. Of course you need help. Hell, even the more seasoned vets have their issues, too. Is it possible you are mono? Maybe. You could be flexible and able to be happy in either style. I was a polyamorist for 18 years, and when I thought I was going to lose my husband, I discovered I was better suited for a closed relationship. I have been in a "mono" marriage for almost eight months, and it is daunting because I have unknowingly stumbled upon my "happily ever after." This certainly was not what I had in mind.
I hope it works out for you, and you should start a blog. I cannot promise that I will comment much, but I would personally follow it. I am rooting for all of you. I hope you get some clarity with the future talks and just self-introsepction. Sending hugs your way.
Ry - Me. Panromantic demisexual with a history of polyamorist tendencies. Married to...
Matt (Hubby) - The once distant stranger that I complement beautifully. DH of 12 years and father of our (3.5) children.