I was reading a story an hour ago and can't find it in my history, 99% sure it was on this site.
A guy comes home and has an accident, his girlfriend notices and is sympathetic, has picked up on him having accidents before but not mentioned it, has a load of diaper supplies ready for this moment and starts babying him. Takes him to a park and he notices two girls/women his age who are wearing the same diapers, think it is Huggies Big Kids, and they come over to watch him get changed.
Tried searching, can't find it.