Dear Mr./Ms. Bossname,
Wow! After all these years, and all the friendships made, I am leaving XYZ Company.
As I pack up my desk (So. Much. Stuff), I’m a little teary-eyed thinking back not only on projects completed and clients secured, but babies born, marriages started (and ended), and so many other things.
It doesn’t feel like I’m quitting a job; it feels like I’m leaving a family.
I thank you for being a great boss, but I thank you even more for being a friend. I know that this won’t be the last we see of each other!