I assume you installed the driver by downloading and compiling the Realtek package. When a new kernel is installed by Update Manager, you must recompile:
cd Desktop/RT8723 <--or wherever you compiled the package
Oops! It errors for me, too. You might try this package: http://www.kernel.org/pub/linux/kernel/projects/backports/2012/12/04/compat-drivers-2012-12-04.tar.gz
./scripts/driver select rtlwifi
sudo make install
sudo modprobe rtl8723ae
You 'make clean' because the module was compiled originally against your specific versions of kernel, headers, gcc, etc. When updates are installed, the various files built in the compile process may or may not work correctly with, for instance, a newer gcc version, so wipe it all out and start fresh: make clean.