Sleeper,
From your posts, I can tell you are a good dad. X obviously hasn't detached. I guess that's an understatement.

Have you considered introducing her to your fiancee? I know this seems stressful but perhaps she will calm down when she has a better sense of who this person is.

As you know, kids are growing up fast and before you know it, X will be in rearview mirror


M: 16 years
Bomb 4/07
OW 20s long gone
Divorced 11/09
I remarried New Guy
Cooperative r w/X regarding D