I went back and looked at the letter you sent your wife. You said it all there. She has a copy of it and can look at it whenever she wants if she wants a chance to come back to the marriage she has a path.
When you interact during your baby's exchanging, perhaps a warm loving look would reinforce what you said in the letter.
Have you seen the movie, Fireproof? Might be inspirational for you....main theme is to continue loving your spouse even when they don't love you back and when you are angry. What she chooses, will be what she chooses, but that doesn't mean you have to stop fighting. Check out youtube to get a glimpse. It is a religious movie as well.
