I've been reading all the information I could find on this subject for over 40 years and this is what I've put together so far. Men are very object oriented when it comes to sexual desires. This is because, at a very young age, nature implants in our minds the objects we will later find to be sexually attractive. Most of us get imprinted with a number of various objects. If these objects are specifically female oriented, such as female breasts, butts, legs, hair, scent, voice, etc., we are considered to be "normal heterosexuals". There is no doubt a strong genetic tendency for nature to favor heterosexual objects when it comes to implanting desires in us, but nature isn't bound by man-made concepts of how evolution is supposed to work. There is no known evolutionary advantage for people to be sexually stimulated by diapers, but there is clearly an advantage to having evolved a mechanism that is flexible enough to include variations, even when those variations defy our beliefs about evolution.
So congratulations! You've been selected by nature to participate in an experiment to see if diaper love is a benefit to our species.
I'm just guessing about why you might be gravitating more towards diapers than women, so take this part with a grain of salt. In a nutshell: you are just being pragmatic about your current situation. You are sexually attracted to diapers and to various female characteristics. These are all imprinted characteristics so they will tend to be strong and permanent. But, for now, diapers are readily available and the perfect female for you isn't. So, for practical reasons, you're shifting your focus. It makes perfect sense.