I disagree a little; I would not put so much emphasis on your partner, would stay with yourself and what you want to say? You have a good start here, could just start out, "Love, I have written this letter because I would like you to know how I feel. . ."

I think you could be getting tangled with trying to stay too far away from your feelings, so you do not upset him? But your "perspective on feelings" makes no sense? You feel; what do you feel?! You don't have to write a tretise on feelings, in general, you only have your own and you sound hurt that your partner will not talk to you for a week, is shutting you out. Tell him that!