"Dear Catherine,
I've been sitting here thinking about all the things I wanted to apologize to you for. All the pain we caused each other. Everything I put on you. Everything I needed you to be or needed you to say. I'm sorry for that.
I'll always love you 'cause we grew up together and you helped make me who I am. I just wanted you to know there will be a piece of you in me always and I'm grateful for that.
Whatever someone you become, and wherever you are in the world, I'm sending you love. You're my friend to the end.
Love, Theodore."