I am kind of doing the opposite of this blog challenge, a letter to him in the event of him dying. It is something that could become very real very quickly do to an illness and I think it will be easier to write in this way...
BFF,
I honestly cannot imagine my life without you in, and I am pretty sure you feel the same way.
For the last nearly 4 years you have been the person I go to for all things sad and happy. I cannot imagine getting up in the morning