I agree with the wonderful point made by Scarlett67. I have kid, but the majority of my (maternal) siblings do not, and will not. Out of six surviving kids (of seven), I’ll be surprised if more the two of us have offspring (me and my brother). The rest… well, the oldest had a child who died in infancy, and never had another. She certainly seems happy. The next knew she’d be a terrible mother (and we pretty much agree), but then married a guy who has not only kids but grandkids, and has found grandmothering suits her fine. The next oldest hasn’t had a stable relationship in ages, and doesn’t want to do a solo parenting thing, on the grounds that she thinks it better to at least TRY for two parents for a kid (though she might eventually consider adopting, her chances are fairly slim). The last childless set might consider it someday, but worry that they are not good parenting material, and also enjoy their life the way it is (and are running out of time, frankly).
All of them are happy, by and large. All of them take their aunt/uncle roles pretty seriously. There’s even one who seems determined to be voted auntie of the year, by sending the BEST presents…
It might be hard to let go of the dream, and I’m sure there has been plenty of greiving involved already, and more to come if you have to change what had been your perceived life path. If it is important enough to pursue it past the hurdles you face, you’ll probably know. But don’t fear you will have no lasting influence on the world for lack of technical progeny. You can change a child’s life immensely, regardless, and make the world a better place. I can’t count the number of people who influenced me as a child - many of them childless. If you place yourselves in a position to be there for a kid (or kids), you will find that the love you have to give will indeed come back to you. And you may find yourselves called to adopt an older child, even. You never know.