these seem to be the salient parts. it looks like as long as both people are in agreement, it can go pretty quickly:
Illinois no longer recognizes "grounds" for divorce. There is only one option: "irreconcilable differences." Irreconcilable differences needs little definition. Technically, to be granted a divorce, one must prove:
irreconcilable differences have caused the irretrievable breakdown of the marriage;
past efforts at reconciliation have failed, and
future efforts at reconciliation would be impracticable and not in the best interests of the family.
750 ILCS 5/401
The Six Month Separation Period: You can live together, file for divorce, finalize it the same day you file, and go back home and continue living together. The six month separation period is not a requirement -- it is an option. Living "separate and apart" for at least six months creates an irrebuttable presumption that irreconcilable differences have caused the irretrievable breakdown of the marriage.
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Skipping the Waiting Period: If you want to get divorced NOW and don't want to wait, that's easy enough. You need only prove the three elements laid out, above. It's simple if you both agree. You may use our Quick Online Divorce service and we'll give you a script to read to the judge at your hearing; or you may hire us to represent you in court. You'll answer 20 questions; every answer will be "yes;" ( "yes . . . yes . . . yes . . . yes"); and you'll walk out divorce. It takes about ten minutes.