My advice to you specifically, @tedd, is to change how you think about this. And I’ll give an example from my own life to illustrate what I mean.
When I was much younger, after having learned to sail and enjoy that, and then reading books like Tinkerbelle, and Gypsy Moth Circles the World and other books by single-handed sailors on epic voyages, I decided that I wanted to sail my own epic voyages. I wanted to single-hand a small boat of my own across the Atlantic. Kids? Eh, I figured I’d get married and have kids or not have them; they didn’t figure so much in my planning when I was much younger.
Well. I’ve done a lot of sailing, but no epic voyages. I got married and we had the kids. I was happy to go along with my wife’s strong desire, and figured I could be a ‘good enough’ dad. I eventually completely changed my focus to ‘being the best dad’ and ‘having the best family that we could have’. I spent a lot less time sailing than I thought I would. The kids are now grown and gone and only close in a figurative way. I’m still capable of sailing, but the epic voyage is less and less likely now.
That change in focus has certainly not ruined my life. I don’t resent my kids for getting in the way of an earlier childhood dream. I’ve enjoyed my kids (and in earlier days, my wife, too) immensely. (I still enjoy the kids.) I might still sail someday; that’s certainly not completely out of the question. My life is just fine, even with the bypassed earlier dream.
It’s certainly commendable to have dreams and to make plans and then proceed along paths that are congruent to those plans in the attempt to realize the dream. That’s what makes us human. But as someone said once, “Life is something that happens while you were making plans for something else.”
Go with the flow, in other words. Take the pressure off your girlfriend and allow her to continue to have her own “well, that wouldn’t be so bad… to… yeah, I really want to do that” realizations. In the meantime, enjoy what you have, and (a personal recommendation from me) learn to sail. That is, enjoy the succession of moments of “now” with her. (You may also find alternate substitute activities to raising children until that time comes – or in case it never does.) Because the other reality is that maybe you’ll find that one or both of you is infertile anyway, and all of this discussing and convincing and (maybe a little) cajoling is for naught. Life may have other plans for you. So go with that. Enjoy what you have while you have it, continue to make your plans and (maybe) new dreams if life takes you that way, but don’t make a decision right now about what must or must not be in your life for it to be happy, successful and worth having “just the way it is.”