My first break up

I want to break up with my girlfriend of 11 months, i have written a well planed and thought out letter, unorthodox i know, but i felt like a letter would avoid more conflict and maybe if she was reading why i felt the way i do you would be more level headed and less likely to lash out and miss my message altogether, i really feel like if I'm going to do this that this is how I'd want to do it. Is it a bad idea? She doesn't live far away i just don't think i can do it face to face, and i know I've heard that text message break ups are awful and the same with over the phone but is this just as bad?