As a political science major and a lawyer,I believe it is crucial to assert your rights. You are not begging for their permission. Their permission is not important. You possess the authority to grant your own annulment. A vent letter may be appropriate depending on circumstances.
Twelve Step groups encourage people to write such letters and then to burn them or throw the pieces in a lake or the ocean. People devise their own rituals with ceremonies that they like. Do something naughty with champagne. Do it with flair.
Writing it as notice rather than request makes you stronger. It also gives them no room to maneuver. We are so used to blind authority. When I started to do unJW things, I felt so awkward. I felt guilty and wonderful at the same time.