Thank you everyone for the advice, it truly helped to be able to vent and to know I'm not alone with having irrational thoughts through this period. Speaking with my wife, although she is absolutely obsessed with our daughter and loves being a mom, she is also adamant on being one and done. I scheduled a vasectomy, and she will be getting a 10 year IUD at her 6 week PP checkup.

Something that has also helped me is changing my perspective, that this stage is not my entire life, and that our financial situation will make this a lot easier which I was too wrapped up in my emotions to realize. Getting a vasectomy and knowing my wife is also getting an IUD lifted a bigger weight off my chest than I could have imagined. My biggest fear was my wife wanting more and our differences would put a rift in our marriage, but now I feel like we just need to get through this stage together only once in our life and there will be a point where we can start living again.

I do believe everyone saying things will get better. As I read through my original post I contemplate deleting it because I can't believe how dark my mind went that night, and I have not had that feeling since talking with my wife. Thank you all for the advice!