I'm all for 180's....did you SEND that letter/e-mail yet?
If not, why not let a few old hands here take a shot at editing it some to convey the same message with a tad less venom.
IF that is you actually hope in some part of your heart that he just MIGHT wake up, smell the coffee and start doing some 180's of his own.
You see, the way you put some things would make it HARDER for him to choose that option. Your anger is valid! ...but should it get in the way of a possible reconcilliation?