Before I jump into this fray, I think that we need the complete birthdata for both people in question.
Speaking as another card-carrying member of the class of 1976, I know that there are some interesting configurations going on through transits and progressions for our particular age group. For example, transiting Saturn is affecting both your Sun by opposition (depending on orb) and Uranus by conjunction. The orb can't be accurately determined through the emphemeris alone.
Also, if you have Mercury retrograde in your natal chart, this might be an ideal time for you to file because the retrograde energy matches your natural Mercury retrograde energy.
More importantly, one needs to see the interaction between all the aspects to understand the complete energetic picture surrounding the possible divorce.
We will be able to give you much better information to help you decide when the best time to file for divorce would be if we can put all the astrological tools together for you through having the complete chart.
And, just remember, it takes two to tango. You are also going to be given information about yourself within the relationship which you might not want to hear. A relationship needs honesty and objectivity and the ability to see the role you play within it. You aren't 100% victim and she isn't 100% villan. The birthdata will show us the interrelationship between the two of you and where each of you play victim, villan, martyr, hero to the other. It will be done objectively because we don't know either of you.
My 2¢ worth, take what's useful and ditch the rest.