pem, no offense but i'm not going to read your letter, it's way too long and will be too tough to breakdown. of course after whatever replies you get you can always send it as is and if this is still what you feel comfortable w/then i say go for it.
take what i say w/a grain of salt because i haven't read your letter but there are some things to consider and i'm sure more people will come on board and give suggestions. i may be totally off base but a plan B letter is not the place to bring up all the past hurts done by the WS, it's not a place to educate, LB, make statements which could ultimately be held against you, or make you out to be a liar. you always have to follow your words w/actions. i say this because when you talk about unconditional love. if he never comes back can you really honestly say you will always feel the way you do? especially if he decides to get really mean, gets someone pregnant, takes you for all you have, etc.
at the same time i know that you are not really doing a plan B letter but i think you should still do as close to that as possible. you have to be careful about telling H what things you are going to do or not going to do because you don't want anything to be used against you. this includes telling any family members or friends that may act like they are on your side but turn around and tell the H everything.
again, if it felt good writing it and after all the replies you receive you still feel that you should send it as is then go ahead. i just hope that you will not look back and regret it. a lot of what we BS do is just that, doing things and acting in a manner in which we can look back and not regret how we handled things. unfortunately, while our S are in whatever fog they are in, letters and conversations cannot be about us and how we feel, how we think things should be, what's fair, etc. even though we are hurting the whole time just the same. do you want to be right or do you want to be married? (that's not originally from me).
good luck and prayers to you, RR