I did not feel ready, and perhaps that is when things started going truly sour. We agreed to bring our amazing first into the world, but I think she expected me to be more excited right out the gate.
I'm sure that there are a million ways I could have handled the situation better. I don't think I quite understood the anxiety I was subjecting her to, with my choice to pursue non traditional income. So rather than hit the street trying to get a job in a country where I don't speak the language, or accept 25% of what I was worth for hourly work, I decided to start an online business.
These two points are probably more important that your realize. Despite the first pregnancy being unplanned, your wife probably did expect you to be more excited and step up to the plate by providing security in way that met her expectations. Your choices likely compromised that desire and trust, and this is likely when a small amount of resentment set in.
Unfortunately for you, it looks like it eventually lead to apathy. Things were fine as long as you met her expectations, and in your case the pursuit of traditional roles.
Your insistence on taking entrepreneurial route at the start was likely your attempt to exercise some sort of control in your life, as the pregnancy threw your plans out the window, and there was also probably some resentment on your behalf.
Seeing a therapist/counselor now is paramount.
Your wife will have felt that she has stood by you while you pursued your desires, and in some ways sacrificing her security. You are in a position now where you are attempting to use sex as a bargaining tool and she is resenting you for making her feel guilty and forcing her to choose when she now also feels like she has regained some control in her life and finally has some time for herself, to do the things she wants.
It may not be so popular, but there is no reason she could have also taken some responsibility in her desire for financial security and you could have been a SAHD while pursing your entrepreneurial goals.
There is an interesting expectation of what a partner feels they deserve within a relationship. Conforming to her expectations has likely come a little too late for her, and resentment only amplifies that self-serving feeling.
I hope things work out for you. 6 years and 2 children with the ups and downs of life in general... Apathy is a real killer and it sounds like she has checked out.
On a side note, Crossfit has a community atmosphere. She will be getting attention and encouragement without the baggage, without anyone wanting something from her. Keep that in mind and consider the dynamics of your relationship when you are at home together. She is living a separate life, which in some ways is a fantasy, from the one she has at home.