feels to me like you do not want children bad enough... there are infertile couples out there who have to pay quite a lot of money to get to the position where you are now (I assume you both guys are fertile) [0]

Apart from the examples in the article, I am also judging from my own experience and I personally reached the point where the money simply does not matter compared to the possibility of being a parent.

0 - https://www.self.com/story/the-cost-of-infertility

Edit: Also agree with others about potential relationship problems you guys may be experiencing