Geepers!
I have worked in dental surgerie that do the kind of work you are talking about and see nthe fab results but that sounds like a hell of alot of money and i hope that they have given you options of prepaying and getting a substantial discount etc.

You are right that being pregnant (all the relaxin) messes with every part of your body - even your teeth and all their connective tissues and ligaments - your gums especially cop it with pregnancy for some reason!

Can I ask??
How many '2nd' opinions did you get??

What sort of crowns are they going to do? I just hope they are planning on using something that will take the brunt of your grinding etc.

Have you tried hypnotherapy for your bruxing/grinding? -seen GREAT results

Been to a Chiropactor who does craniosacral massage? - really helpful and I would say neccessary in this type of dental treatment.

Sorry to be so nosey - i just dont want to be giving the wrong info here!
I have been in the dental game for a while now and am more that happy to even talk to my boss about your case if you like - My boss is a special needs specialist dentist which means we basically see all the patients nobody else wants to coz they go in that to hard basket!