>>2561479
3. If she already has kinks you need to focus very hard on finding parallels with that and ABDL. Find ways to incorporate stuff she likes into the stuff you like. Even if she doesn't have specific kinks, are there any scenarios or fantasies she has? Ask her. And then try to see if she would be open to incorporating diapers or ageplay into that. This is way easier if she's submissive or has related kinks like spanking or humiliation.
4. Similar to the kink thing, any interests or hobbies she's into figure out if it's possible to incorporate ABDL with that. Or possibly approach it from that angle. If she's an artist or likes to doodle, maybe she would enjoy drawing on a blank white diaper. I had an ex who was really into fashion, and although it took a while, she did eventually come to like the idea of coordinating cute ABDL outfits. If all she likes to do in her free time is play games or watch anime or something, maybe you can just convince her to wear diapers while she does that. The hope is that she associates diapers and ageplay with stuff she enjoys and finds comforting.