Grizz I think if it makes you feel better and you feel that you don't want anything left unsaid before she moves then by all means send it.
Like Urworthy said, if your head is in the right place then that is what matters.
I wrote a letter like that in mid February while I was at a salient retreat for 3 days with the advice of a priest. It did feel good to get it out, but she wasnt ready for that now that I know shad just spent weekend with OM a few days before that. Looking back I feel embarrased for sending it. At the time I felt just like you and felt I had to get it on paper.
Have no expectations of a reply that's for sure


M 37 W 30
S 7
Together 10 years
Married 9 years
BD: 12/12/12(W filed same day)
I moved to apartment 1/11/13
W and S moved to MIL 1/11/13
Peicing: 6/3/13
Reconciled: 7/2013
BD2: 4/20/16
still working on it