NMC, two very basic issues that you want to figure out is (and you may already know) ... are you in a no-fault divorce state? Are you in a state that requires a period of separation before a divorce?
True. I am in a no-fault state, but the affair stuff and other info was still used against her. In some states (mine), the period of separation is defined as marital relations being stopped - no sex, etc - for a certain period...in ours, there is no separation agreement sort of thing.
There are moments in this life when you are so confident in the rightness of your actions, that not even for a second do you consider the option that you might be wrong.