Most Helpful Guy
I don't think your reason is wrong, I wouldn't date someone I'm not attracted to, I tried and it was a huge mistake.
But I do think your attitude does make you sound like a bitch, I mean, you can just say you don't like the fact he looks younger than his real age, and don't say "I wanted a man, not a little boy in diapers", calling him a little boy in diapers was unnecessary, you're devaluing him just because you're not attracted to him anymore... I think you actually did him a favor by breaking up, your attitude sucks.
Most Helpful Girl
... I see no point in being in a relationship with someone I'm just not attracted to anymore.
Allow Me, this wise ol owl, to take some of the baby burden off your shoulders here, dear. I find you are this Honest Jane in Openly Admitting all of this, and not only That, very Mature in breaking it off, rather than continue to Pretend By... Pulling it off.
Good luck. xx