@Baldimo,
Hi Baldimo, I am at the tail end of a very similar story. My wife was also Christian and her inflexible ideas on how things had to be were a part of the problem (she was upset that I let our children celebrate Halloween). Of course, it is never just one thing, but I sympathize with how you are feeling.
I also decided I wasn't going to keep bending over backward for her beliefs. I first moved into the living room, at that point I was truly trying to find a way to make things work. After 4 months of this, I moved out to my own place.
If I can give any advice from my experience, it is act quickly and decisively. The more you dither, the harder it will be for both of you. I asked my wife to go to counseling with me (I think this was a good thing to do). She refused, and after a few more fights I finally decided it was time to move on.
It took me a long time... too long, to file for divorce (in our case there was another issue that complicated things, but waiting was certainly a big mistake).
The other really important thing is to make sure you are decent about the children. One of the best things my wife and I both did during this process is to say up front that it isn't the kid's fault, and that both of us would keep the kids out of this. My wife and I have both done a good job with this.
We have our trial in October, we are trying to use a mediator to come up with an amicable settlement. I am grateful that our kids are doing OK and that both of us are at least being decent in this regard.
In my case, filing for a divorce was the best thing for all involved because it stopped the games and let us focus on healing. I should have filed as soon as it was clear the marriage wasn't going to work.
Best of luck. There is life after divorce.