fixing glitches and making DLC takes up time , adding the marriage option is a few clicks of adding the same voice actress at the very least. alothugh granted id like some unique vamp marriage dialogue.
and if the line were never recorded to bein with they have to find the actress, ask her to return, discuss pay, timing, affectivly writing/rewriting a contract, record the new lines, put them in a patch for us. its more than just a few clicks....