Reure my Mother about 2012/2011?

Okay so recently my dad has been talking all crazy about the world ending, and I've been noticing my mom rather down. It kills me to see her that way, and honestly I'm starting to feel that way too. I know there are so many questions about this, and my apologies, I bet it's tiresome going through the same questions and answers but I need to reure my mom that it won't happen. Any ideas?