I had the same problem, even after taking 2 castles and requesting them.
Eventually I just saved my game, went to Harlus and renounced my vows (after taking everything I wanted out of my castle storage).
After that, I was unable to find my wife, but I figured meh.
Luckily for me, I ran into Lord Irya outside of Wercheg and convinced him to support my claim to the throne, so I got Werchegand named her my Minister, so I got her to show again.
Now if only I can figure out how to name a new capital, I'll be set.
Edited because I have a MMO on the brain (Warbug = Wercheg)
