I have no intentions on filing these out because I do not believe the marriage can't be saved. Any advice on how to tell her this?
So the general DB'ing attitude is don't do anything to block the D, but don't go out of your way to help. Let her fill everything out. If she needs something that only you can provide (W-2 info or such) then provide her with the info. If she asks for help with the papers just tell her "this is not what I want but I understand that it is what you want so I will not try to stop you, but you need to do all the work because my heart isn't in it" or something along those lines.
