A default is only filed if you failed to answer the papers served on you by your spouse. Answering those papers is the way to contest something in your divorce. Not answering and defaulting in most cases prevents you from contesting anything.
All is not lost; the Court generally favors contested litigation. Depending on when the Request for Entry of Default was filed and why you failed to Respond to the Summoms, the Court may vacate the Default. Another question is whether or not a Judgment is already filed.
This is not legal advice nor does it create an attorney-client relationship. This information is general in nature. You should consult an attorney directly to analyze your individual situation and advise you accordingly.
When default was entered and why you failed to appear will determine whether or not you can have the default "set aside". For the default to have been entered, you should have been given notice of the request for default and the default hearing. It takes time for this to happen. If default has been requested but not yet entered, you can still go in and plead the matter - the judge will most likely allow you to respond. If default has already been entered (judge has already ruled), you will have to file a request to set it aside and go into explain yourself. Again, the judge will likely allow you to respond, but it depends on the situation.