Yes after the order of ex-parte divorce yourwife can anytime appear in the trail court move application under Order 9 Rule 13 CPC for setting aside decree of divorce. No time frame for moving the setting aside application but the respondent wife will be required to show and satisfy the court as to why she was unable to defend the petition for divorce even after she was served with court notice.
The appeal in the High Court against the district court order granting decree of divorce to you can always be second option for your wife but in that case too she will be required to show and satisfy the High Court that the trail court committed apparent error of law while deciding the divorce petition in your favor. In appeal the ex-parte evidence that was not contested by you cannot be challeged but the error of law committed or ignored by the trail court will always be open for the respondent wife, 90 days is time period within which appeal should be filled but any delay in this can also be got condoned by moving application for condonation of delay by siting relavant reason for the same.
The trail Family Court usually allows the setting aside application under order 9 rule 13 CPC in most cases thus allowing the respondent spouse to bring on record his/her case defending the divorce petition the trail Family Court.