a letter to my s/o

Fall 2016
My greatest fear is not that you'll cheat on me. I may have trust issues, and I may struggle to tell you everything, even though we promised complete honesty. But I know your character, and I know your heart. You would never do anything to hurt me. I also know I can trust you because you are a man of your word, and that once you put your mind to something you don't give it up (a nicer term than "stubborn butthead").
My greatest fear is not that you'll cease loving me. Although sometimes I doubt your love (through no fault of your own), and sometimes I think you don't know what you're getting into, deep-down I do believe you when you say that you love me. I believe you when you say you'll always love me. I believe you when you say our love is forever.
My greatest fear is not that you'll change. You will grow - you'll be a stronger person, you'll draw closer to the Lord, and you'll learn new things. You will become even more independent than you already are as we establish ourselves as a couple living on our own. Through the years to come you will gain wisdom and knowledge. But your intrinsic character won't change - your sense of humor, your bluntness, your logic, your honesty, your nerdiness, and your determination will remain.
My greatest fear is not that you'll stop calling me beautiful. You have destroyed my definitions of beauty - I used to wonder who could love someone like me, with too many scars to count, a disabled body, and muscles that don't really exist. But you told me my scars were beautiful, and that you loved me, all of me, even my [big] butt. And over time I have learned to believe you.
My greatest fear is not that I'll cheat on you. I love you with all my heart. I would never do anything to hurt you, and I would never want to be with anyone other than you.
My greatest fear is not that I'll stop loving you. Although in the past I have told you that I don't know how to love, I try to love you to the best of my ability. 
My greatest fear is not that I'll change. The past year has been a hard year for both of us, but you have supported me through it. Although sometimes I fear for the person I might become, I know that my faith, your love, and the support of others will guide me back to the person I am truly meant to be, no matter how far I might stray.
My greatest fear is not that I'll stop believing you are the cutest guy on the planet. :) Benedict Cumberbatch might have some nice cheekbones, but I will always prefer you. When we first began our relationship and I was sitting at the counter top with Mom discussing courtship, she mentioned that physical attraction was an important, though not the primary, element. I assured her that it was no problem, and that has not changed. There are still times when seeing you makes my heart leap unexpectedly, and the familiar butterflies return to my stomach. No, my greatest fear is not that I will cease calling you handsome.
My greatest fear is not that we'll lose interest in each other, that we'll stop loving each other, that we'll change, or that we'll cease being attracted to each another. 
I want to marry you. I want to have children with you and grow old with you. But I fear that somewhere along the way, we will slowly fall out of love with each other. Not the kind of disinterest that results in cheating or separation or divorce. Not the kind of disinterest that causes major marital difficulties. Not the kind of disinterest that friends or family or even our children could really notice. It will be a gradual process as our love that was once passionate, instead of maturing into something even more beautiful, slowly dulls and fades. It will be so subtle that we will not even notice - it will perhaps just be a small niggling at the back of our minds that something is different, that something is wrong. But it will never be enough to cause more than a small discomfort.
My greatest fear is not that we will slowly fall out of love with each other.
My greatest is fear is that we will slowly fall out of love with each other and that   we won't even notice.