You must apply to USCIS for an exemption/waiver of the 2-year requirement. The sooner, the better. Your wife started accruing illegal presence in the Country and might be penalized (the tree/ten year bar). Would be good if you could show a "good cause," i.e. circumstances beyond your control, to file the I-751 timely. In any way, be honest and USCIS may forgive you, especially if your marriage is preserved. I would suggest to consult an attorney about your circumstances, because if your request is denied, your wife might be referred for removal action (if not already).
Answered on Apr 22nd, 2013 at 8:36 PM