So you know how lifespan after undeath doesn't count for shipping purposes?

Which is why it's not skeevy at all for a 457 year old man to date a 18 year old woman so long as he was 20 when he turned, because he's still 20 in every meaningful sense?

Logically speaking, though, that's gotta cause problems at the other end, when the 38 year old woman looks around and realizes that the man who was mature and sophisticated when she was a teen is now very not, and she's thoroughly outgrown him.

I don't think enough people really think this one through. Unless you're willing to be turned into a vampire, you probably shouldn't make any long term commitments.