you are lucky fellow that your wife is asking divorce-------just think reverse when you need divorce and your wife will pull your legs and don't let you to go away snatching your all peace and freedom with hard earned money through mainetanance then what would you have done?
Now come to the reality if there is no proof then let her fight at last she will come to you for negotiations and she will offer you MEGA DISCOUNT on not your freedom but on her freedom. So wait for that moment.But make a note a person whose tendency is to go away can't be asked to remain with you a longtime.
Better leave on her own thinking.Both side you are safe.