Upload & Sell: Off
Bill them but it sounds like you signed, they signed, you shot it so it's far far too late though. At the price and standard contract you use the pictures, with their demands you can't so they should pay more for that. If all couples did this you would have a website with nothing on it, a facebook page with nothing on it and blank albums to show clients.
Paging TRR to thread...
Yes, I would have a fee to release levels of usage. If a client doesn't want you to show the work to anyone they are effectively dictating what you can do with your copyrighted material. That's totally fine, but there ought to be a cost for that kind of exclusivity. I am now working on a millionaire's wedding. They spent $250,000 on decor alone. It was amazing, and we can't show it. No problem, because the venue and coordinator know we can do the work and the exclusivity check cleared. Everyone walks away getting what they want.
If this happens once a year I wouldn't necessarily make a big deal about it. Having said that, I think everyone ought to have a policy on how to manage privacy requests. We sell them, and we're happy to do it. I like money better than padding out my portfolio. YMMV of course.