Once you get the wording right, it will be a very constructive letter. I agree with the others that your wife will fight it but you can be proud that you'll have shelved your emotions and tackled the problem thoughtfully and with regards to your wife and kids.
Me: 31, W: 29 T: 4 M: 2 Kids: 3 (SS: 7, SD: 4, D: 3) Separated, still living together: Nov 2013 Separate bedrooms: Feb 2014 W working away; kids with me: Nov 2014
