I'm sorry to hear. I don't know the reason why your financee don't want kids.

I have been very hesitant to have kids for a long time for many reasons. My wife have been wanting to have kids, so have felt quite conflicted.

Then this year I read the book after the spike which put a lot of this in perspective which made the thought of having kids less daunting somehow.

https://www.barnesandnoble.com/w/after-the-spike-dean-spears...

I wish both of you well in how you navigate the path forwards.