Ten years is not a huge age difference, after all. It is when one of the partners is nineteen. Most nineteen year olds and twenty-nine years old have little in common. Obviously, Donna and Terry could be the exception, but their interests are never really explained.
I'm trying to remember - I remember reading a post-WW-reboot version of the wedding scene in which Kory is the maid of honor - anyone remember what that was from? The only recent version of the wedding scene I can remember is from JLA #0, but I don't think that's what you're referring to. Kory's not the maid of honor, anyway.