For me my ABDL side is about as non-sexual as possible for a person that is not completely asexual. I have never engaged in diaper play of any kind with another person, and I almost never masturbate during diaper play because I've found it's not worth the feelings of shame and disgust that follow my climax. My first memory of diaper desires was when I was 4 years old, and my desires are as strong as ever and I am now 31. When I was in the height of puberty I admit I got a little more of a sexual thrill from wearing, but now that I am lucky enough to wear often enough the novelty has worn off along with my teenage sex drive.
Now, if a beautiful young woman were to change me in a babysitter's role, I would probably explode with sexual tension. But on any ordinary diaper day, its an emotional release and escape, not sexual.