I know what you're going through, there are days when I wish I thought diapers were weird and just liked boobs like everyone else. (Not that I don't like boobs.)
But you have to remember, as long as it doesn't become an obsession that starts interfering with the rest of your life, it's fine. When you don't have rent money because you spent it on diapers, that's when you might want to reconsider it.
Everyone likes to spice up their life with SOMETHING, even if they don't admit it. Diapers aren't some crazy alternative to sexuality, they're an accent. They're a choice and a form of expression, just like a lot of other stuff in society. You'll find that the ABDL community is just as diverse as any other if you examine it. Some people like messing, some people get disgusted by it, some people get humiliated by being disgusted by it and LIKE it.
Everyone indulges, just do it in moderation and don't let it take over your life.