How do I get rid of a navel/belly button fetish?

Psychotherapy ?CBT. Obsessional ideation can typically be dealt with best with cognitive behavior therapy. Thought stopping is strategy where when you start to obsess, you close your eyes and visualize a large re stop sign and shout to yourself, "stop." intentional distraction can be effective. More analytical type therapy would focus on origins and "what does this mean?" approaches. This would likely be helpful.
It depends. It depends on how much it bothers you. Or maybe it doesn't bother you much and all and you actually kind of enjoy it. There are things called obsessions and then there are what are known as habits. One main difference is that we enjoy some of the habits we have and dislike others. Obsessions are uncomfortable. It also depends how much time a day you spend on this.