I do not know much about the legalities of things as they vary from State to State. But I do know that Divorces can be contested. From what you have posted you have to sign and return the papers in 21 days, that is IF you agree to everything. If you do not agree to whatever you have received then your Lawyer can respond and this will buy you more time. If however you have changed your mind and it is all clear cut and dried, then only you can make the decision.
There can be no testimony without a test. I am praying to go through this test and come out the other end with a new and better marriage then before.
