Too quit a diaper fetish or any other fetish is really hard. But I'm sure it's possible.
You can try quitting cold turkey by getting rid of all your diapers and not looking back.
But I do hear most return to there diapers. A psychologist might be able to help.
If you don't succeed though. Remember that there are lots of other fetishes out there besides loving diapers.
Some love feet, some love trees. Literally some people will have sex with trees. Then there's that one lady I believe who married a carnival ride because she has a fetish for carnival rides.
We all love different things and there's nothing wrong with it.
The world would be really boring if we were all the same and had the same interests.