Assemblies automatically save when referenced drawing is open

Does anyone know if there is a way to keep assemblies from updating automatically when a referenced drawing is open.  For instance, I can have both an assembly file and it's referenced drawing open, hide a particular part in the assembly so that I can view objects behind it, and close the assembly and choose not to save it.  The only problem is that when performing those actions it does save the assembly.  Also, if there are sub-assemblies in the assembly then there is even a greater mess.

Thanks.

SolidworksAssemblies