but id does happen all the time,
school girls dating college guys
old rich people dating younger folk
perhaps people do it because they feel the age of the person they are dating was the best years of their lives and they can become that person yet again when they get into it. There are plenty of references of people saying they act like teenagers again when they find young or new love, this might just be an example of it, plus the whole taboo of it drives the attraction.
i think it's plausible, maybe not always right but plausible.
i do know what you mean about dating someone not in the same frame of mind as you. Simply changing from an undergraduate to a post graduate and dating an older woman, living on my own and fending for myself. i've suddenly gotten the impression that even people a couple of months younger than me are completely in a different place than i am.....they are still hot though....